diff --git a/docs/parity/03-email-viewer.md b/docs/parity/03-email-viewer.md
index bda8256a..45dd2ce8 100644
--- a/docs/parity/03-email-viewer.md
+++ b/docs/parity/03-email-viewer.md
@@ -12,7 +12,7 @@ RN has a solid single-message reader (WebView body with CSP, shrink-to-fit + pin
   - What RN does: the list collapses same-thread rows to the newest message with a count badge (`src/screens/EmailListScreen.tsx:224-238`, default `disableThreading: false` at `src/stores/settings-store.ts:266`), the row opens `EmailThreadScreen` with a single `emailId` (`App.tsx:145-151`), and the screen only ever shows that one message (`src/screens/EmailThreadScreen.tsx:113-120`, `685-840`). `getThread` exists in `src/api/email.ts:448` but is only used by a test. Older messages of a thread cannot be opened at all unless the user turns on "Disable Thread Grouping".
   - Fix hint: on open, call `getThread(threadId, ownerAccountId)` + `getFullEmails(ids)` and render a vertical list of collapsible message cards inside the pane (newest + unread expanded), reusing `EmailBodyView` per card; keep the horizontal pager for thread-to-thread navigation.
 
-- [ ] **Pager shows the wrong message (or nothing) when the opened email is not in the store list** — `P1` — `rn-only-bug`
+- [x] **Pager shows the wrong message (or nothing) when the opened email is not in the store list — fixed in c8be383** — `P1` — `rn-only-bug`
   - What WEB does: the viewer renders `selectedEmail` directly; prev/next are derived from the current list (`components/email/email-viewer.tsx:5220-5279`).
   - What RN does: the pager is a `FlatList` over `useEmailStore(s => s.emails)` and the initial index is `Math.max(0, emails.findIndex(id))` (`src/screens/EmailThreadScreen.tsx:128-133`, `535-572`). `UnifiedInboxScreen` keeps its own local list and never writes the store (`src/screens/UnifiedInboxScreen.tsx:35-50`, `61-84`), `ContactActivity` navigates with ids from a contact search (`src/components/contacts/ContactActivity.tsx:170-177`). In both cases the opened id is absent from `emails`, so the visible pane is `emails[0]` (a different mailbox's first message, or blank when the list is empty) while the toolbar/mark-read/delete act on `activeEmailId`.
   - Fix hint: when `route.params.emailId` is not in `emails`, render a single-item pager (`data=[{id: emailId}]`) and disable prev/next; or have the unified inbox / contact activity pass their own id list through route params.
@@ -26,12 +26,12 @@ RN has a solid single-message reader (WebView body with CSP, shrink-to-fit + pin
 
 ### Body rendering & sanitisation
 
-- [ ] **HTML-only messages are rendered (and quoted) as raw HTML source — native issue #46 "email preview shows css"** — `P1` — `bug`
+- [x] **HTML-only messages are rendered (and quoted) as raw HTML source — native issue #46 "email preview shows css" — fixed in 06742ef** — `P1` — `bug`
   - What WEB does: per RFC 8621 §4.1.4 an HTML-only message exposes the same part in `textBody` and `htmlBody`; WEB checks `hasDistinctTextBody` (different partIds) before preferring the text alternative, and routes by the part's `type` (`components/email/email-viewer.tsx:1727-1747`, `components/email/thread-conversation-view.tsx:332-346`; changelog 1.6.3 "Render HTML-only emails", "Render plain-text-only emails as text, not HTML").
   - What RN does: `extractTextBody` returns the html part's value for HTML-only mail, then `rawHtml = html && (!text || hasMeaningfulHtmlBody(html)) ? html : null` (`src/components/EmailBodyView.tsx:43-57`, `504-511`). For any HTML-only message whose markup fails `MEANINGFUL_HTML_RE` (`src/lib/email-html.ts:353-362`, e.g. a `<div>`/`<p>` body without `style=`), `rawHtml` is null and the raw source — tags, `<head>`, CSS — is shown as plain text. The same value feeds the reply quote: `plainTextBody()` (`src/screens/EmailThreadScreen.tsx:59-65`, `377`) so replies to HTML-only mail quote escaped HTML source.
   - Fix hint: compare `textBody[0].partId !== htmlBody[0].partId` (and `part.type === 'text/html'`) before treating `text` as an alternative; in `navigateCompose` pass `htmlBody` (and let `buildInitialHtml` use it) or convert with `htmlToPlainText` (`src/lib/compose-html.ts:108`) when the only body is HTML.
 
-- [ ] **`<style>` blocks are stripped from every HTML email — layout/colour loss, likely native issue #49 "Unreadable text in dark-mode emails"** — `P2` — `bugfix-parity`
+- [x] **`<style>` blocks are stripped from every HTML email — layout/colour loss, likely native issue #49 "Unreadable text in dark-mode emails" — fixed in 06742ef** — `P2` — `bugfix-parity`
   - What WEB does: iframe sanitiser keeps `<style>` (`lib/email-sanitization.ts:60-78`), and when external content is blocked it neutralises `url()`/`@import`/`@font-face` inside the sheet (`stripExternalStyleSheetCss`, `lib/email-sanitization.ts:474-509`, changelog 1.7.8 #457) while the strict iframe CSP is the network backstop (`components/email/email-viewer.tsx:2265-2267`).
   - What RN does: `FORBID_TAGS` includes `'style'` (and `svg`) so every stylesheet is removed before render (`src/lib/email-html.ts:16-28`, `50-68`). Class-based colours vanish: a newsletter with white text via `.hero { color:#fff }` on a `bgcolor` cell renders white-on-white (light) or, after the invert filter, black-on-black. Also `hasNativeDarkMode` is evaluated on the *stripped* HTML inside `wrapEmailHtml` (`src/lib/email-html.ts:226-229`) but on the raw HTML in the component (`src/components/EmailBodyView.tsx:612-613`), so for emails with `@media (prefers-color-scheme: dark)` the CSS inversion is applied but the DOM re-invert pass is skipped.
   - Fix hint: keep `<style>` (the WebView is an isolated document; CSP already has `style-src 'unsafe-inline'`), port `stripExternalStyleSheetCss` + `decodeCssEscapes` for the blocked case, and evaluate `hasNativeDarkMode` once on the same input.
@@ -41,50 +41,50 @@ RN has a solid single-message reader (WebView body with CSP, shrink-to-fit + pin
   - What RN does: `DARK_INVERSION` applies the `:not(:has(...))` guard to background-image containers too and includes them in the nested `filter:none` rule (`src/lib/email-html.ts:167-185`), the DOM pass only re-inverts containers without media children (`src/components/EmailBodyView.tsx:72-88`); no Word/Outlook padding, no per-message light/dark toggle (WEB toolbar Sun/Moon, `email-viewer.tsx:3199-3212`, changelog 1.6.0), no `messageSpacing`.
   - Fix hint: copy the current `darkModeCSS` block and the DOM re-invert loop verbatim into `email-html.ts` / `DARK_REINVERT_SCRIPT`; add a "View in light/dark mode" entry to the More sheet that overrides `renderAsDark` for the current message.
 
-- [ ] **External-content detection misses most tracking vectors (privacy leak)** — `P2` — `bugfix-parity`
+- [x] **External-content detection misses most tracking vectors (privacy leak) — fixed in 06742ef** — `P2` — `bugfix-parity`
   - What WEB does: `isExternalResourceUrl` strips C0/space so `"\nhttps://x"` and `h\ttps://` count; blocks `<img srcset>`, `<picture><source>`, `<video poster>`, media `src`, `background=`, inline `url()` incl. CSS escapes, `<style>` url()/@import, and forbids `<link>` in blocking mode; the banner is driven by "something was actually blocked" (`lib/email-sanitization.ts:399-406`, `511-615`, `108-150`; changelog 1.7.8).
   - What RN does: `hasRemoteContent` only matches `<img src="http…">`, `background="http…"` and `style="...url(http…)"` (`src/lib/email-html.ts:364-369`); when it returns false `shouldBlock` is false and the CSP becomes `img-src data: cid: https: http:` (`src/lib/email-html.ts:235`), so a pixel expressed as `srcset=`, `<source>`, `poster=`, `src=" https://…"` (leading whitespace/newline), or a CSS-escaped `\68ttps://` loads unconditionally under policy `ask`/`block`. `blockRemoteImageSrcs` (`316-347`) is likewise src/srcset/background/style only, and has no `data-blocked-*` restore.
   - Fix hint: make the gate policy-driven rather than detection-driven (block = strict CSP `img-src data: cid:` + `media-src`/`font-src` none whenever policy is `block`/`ask`-not-allowed and sender untrusted, like WEB's `externalBlocked`), port `isExternalResourceUrl` normalisation, add `source/video/audio/poster/link` handling, and show the banner when the strict CSP is in effect and the HTML contains any `http(s)://` resource reference.
 
-- [ ] **Blocked images leave broken-image icons / alt text; empty containers not collapsed** — `P3` — `bugfix-parity`
+- [x] **Blocked images leave broken-image icons / alt text; empty containers not collapsed — fixed in 06742ef** — `P3` — `bugfix-parity`
   - What WEB does: swaps `src` for a transparent 1x1 GIF, empties `alt`, `display:none`, and collapses empty `<td>/<div>` wrappers (`lib/email-sanitization.ts:319-320`, `537-546`, `678-704`); hides images that fail to load (`components/email/email-viewer.tsx:2393-2411`, changelog 1.7.7).
   - What RN does: sets `src=""` and `alt="[remote image blocked]"` (`src/lib/email-html.ts:319-323`), so blocked newsletters show rows of broken-image glyphs with English alt text; no failed-image hiding.
   - Fix hint: use the same transparent-GIF + `display:none` swap and port `collapseBlockedImageContainers` as a regex/DOM pass in the injected script; add an `img` `error` listener that hides the element.
 
-- [ ] **mailto: links inside the body open the OS mail handler instead of the app composer** — `P2` — `missing`
+- [x] **mailto: links inside the body open the OS mail handler instead of the app composer — fixed in 06742ef** — `P2` — `missing`
   - What WEB does: `mailto:` opens the built-in composer with parsed to/subject/body (changelog 1.8.1 "Open mailto: links in the built-in composer"; iframe click handler leaves `mailto:` to the app's protocol handling, `components/email/email-viewer.tsx:2420-2436`).
   - What RN does: `onShouldStartLoadWithRequest` hands `mailto:` to `Linking.openURL` (`src/components/EmailBodyView.tsx:715-724`), so tapping an address in an email opens Gmail/Apple Mail instead of Bulwark.
   - Fix hint: parse `mailto:` (address, `subject`, `body`, `cc`) and `navigation.navigate('Compose', { prefillTo, ... })`; the `prefillTo` param already exists (`src/screens/ComposeScreen.tsx:292-298`).
 
-- [ ] **`data:` URL navigations replace the email body** — `P3` — `rn-only-bug`
+- [x] **`data:` URL navigations replace the email body — fixed in 06742ef** — `P3` — `rn-only-bug`
   - What RN does: `onShouldStartLoadWithRequest` returns `true` for any `data:` URL (`src/components/EmailBodyView.tsx:717-719`), and `safeUri` keeps `href="data:image/…"` (`src/lib/email-html.ts:109-113`); tapping such a link navigates the WebView to the image with no way back. Only the initial `about:blank` load should be allowed.
   - Fix hint: allow `data:` only when `request.navigationType === 'other' && !request.isTopFrame`-style initial loads, otherwise return false (optionally open images externally).
 
-- [ ] **Regex sanitiser + `script-src 'unsafe-inline'`: keep the data-URI/SVG allowlist in sync with WEB** — `P3` — `partial`
+- [x] **Regex sanitiser + `script-src 'unsafe-inline'`: keep the data-URI/SVG allowlist in sync with WEB — fixed in 06742ef** — `P3` — `partial`
   - What WEB does: allows only raster `data:image/(png|jpe?g|gif|webp|bmp|avif|x-icon|vnd.microsoft.icon)` on media tags, re-checks `srcset` candidates individually, forbids SVG data URIs and `<svg>` (`lib/email-sanitization.ts:24`, `330-388`), and the iframe has no scripting at all.
   - What RN does: `safeUri` allows any `data:image/*` including `image/svg+xml` (`src/lib/email-html.ts:109-113`), `srcset` values are never scheme-checked except when blocking (`326-329`), and the page CSP must allow `'unsafe-inline'` scripts for the injected bridge (`236-245`), so a parser-differential bypass of the regex stripper would execute script in the WebView (limited blast radius: the bridge only accepts height/swipe/zoom strings).
   - Fix hint: restrict `data:` to the raster list, scheme-check every `srcset` candidate, and consider parsing with a real HTML parser (e.g. `htmlparser2`/`parse5` on the JS side) instead of regexes; document the residual risk.
 
-- [ ] **Quoted reply text is not collapsed (#480)** — `P3` — `missing`
+- [x] **Quoted reply text is not collapsed (#480) — fixed in 06742ef** — `P3` — `missing`
   - What WEB does: hides the trailing quote (Gmail/Outlook/Apple/Thunderbird/Bulwark markers, attributed `<blockquote>`, `>`-lines in plain text) behind a "•••" toggle (`lib/quote-collapse.ts:143-197`, `219-259`; changelog 1.7.8).
   - What RN does: nothing; long threads show every quoted original inline.
   - Fix hint: port `setupQuoteCollapse` into the injected WebView script (runs on the parsed DOM, uses inline styles only) and `collapsePlainTextQuotes` into `wrapPlainTextEmail`.
 
-- [ ] **Plain-text bodies are always monospace (#830)** — `P3` — `bugfix-parity`
+- [x] **Plain-text bodies are always monospace (#830) — fixed in 06742ef** — `P3` — `bugfix-parity`
   - What WEB does: renders text/plain in the app font by default with a `plainTextFont: 'sans' | 'mono'` setting (`stores/settings-store.ts:329`, `565`; `components/email/email-viewer.tsx:5050-5060`; changelog 1.9.0).
   - What RN does: `wrapPlainTextEmail` hard-codes `ui-monospace, Menlo, …` (`src/lib/email-html.ts:290`); no setting (`src/stores/settings-store.ts` has no `plainTextFont`).
   - Fix hint: add the setting (Reading settings) and switch the font-family in `wrapPlainTextEmail`.
 
 - [ ] **Plain-text linkifier only catches http(s)** — `P3` — `verified` (same as WEB `plainTextToSafeHtml`); no action.
 
-- [ ] **cid images larger than 2 MB and non-image cid parts silently show a 1x1 placeholder; octet-stream cid parts (#543) unverified** — `P3` — `partial`
+- [x] **cid images larger than 2 MB and non-image cid parts silently show a 1x1 placeholder; octet-stream cid parts (#543) unverified — fixed in 06742ef** — `P3` — `partial`
   - What WEB does: fetches every cid part as an authenticated `blob:` URL regardless of size/type; the browser sniffs `application/octet-stream` image bytes (`components/email/email-viewer.tsx:1509-1575`; changelog 1.8.1 #543).
   - What RN does: skips parts over `MAX_INLINE_IMAGE_BYTES` (`src/components/EmailBodyView.tsx:15`, `556-559`) and builds `data:${att.type || 'application/octet-stream'};base64,…` (`573`), which Chromium/WebKit may refuse to decode as an image for `application/octet-stream`.
   - Fix hint: sniff magic bytes (PNG/JPEG/GIF/WebP) to pick the MIME for the data URI; for >2 MB parts encode off the JS thread (e.g. `File.base64()` from expo-file-system after `downloadInto`) instead of dropping them.
 
 ### Header / meta
 
-- [ ] **`headers`, `messageId`, `inReplyTo`, `references` are never fetched** — `P2` — `missing` (root cause for the next five items)
+- [x] **`headers`, `messageId`, `inReplyTo`, `references` are never fetched — fixed in ccbe67c** — `P2` — `missing` (root cause for the next five items)
   - What WEB does: `Email/get` requests `messageId, inReplyTo, references, headers, bodyStructure` and parses `Authentication-Results`, `X-Spam-*`, `X-Spam-LLM` into `email.authenticationResults/spamScore/spamLLM` (`lib/jmap/client.ts:1775-1870`).
   - What RN does: `EMAIL_FULL_PROPERTIES` stops at `bodyStructure, textBody, htmlBody, bodyValues, attachments, blobId, bcc, replyTo, sentAt` (`src/api/email.ts:11-15`); the `Email` type has no `headers`/`messageId` (`src/api/types.ts:65-87`).
   - Fix hint: add the four properties to `EMAIL_FULL_PROPERTIES`, extend the type, and port `parseAuthenticationResults`/`parseSpamScore`/`extractListHeaders` (`lib/email-headers.ts`) to `src/lib/email-headers.ts`.
@@ -109,7 +109,7 @@ RN has a solid single-message reader (WebView body with CSP, shrink-to-fit + pin
   - What RN does: none; no `readReceiptResponse` setting.
   - Fix hint: port `lib/mdn.ts` verbatim (pure string builder), reuse `uploadBytes` (`src/api/blob.ts:67`) + `importEmailBlob` (`src/api/email.ts:423`) + an `EmailSubmission/set` helper; add the setting.
 
-- [ ] **Reply-To shown / used** — folded into the reply-recipients finding below.
+- [x] **Reply-To shown / used — fixed in 7f956d6** — folded into the reply-recipients finding below.
 
 - [ ] **Sender / recipient tap actions (popover, view/add contact, copy address)** — `P3` — `missing`
   - What WEB does: every address is a `RecipientPopover` (contact lookup, extra emails/phones, copy, email, view/add contact); tapping the avatar opens the contact sidebar or, on mobile, the contact page (`components/email/recipient-popover.tsx`, `components/email/email-viewer.tsx:1140-1170`, `3841-3866`).
@@ -128,7 +128,7 @@ RN has a solid single-message reader (WebView body with CSP, shrink-to-fit + pin
 
 ### Calendar invitation banner
 
-- [ ] **Invitation parsing is not routed to the owning account (#847, #867)** — `P2` — `bugfix-parity`
+- [x] **Invitation parsing is not routed to the owning account (#847, #867) — fixed in 8206893** — `P2` — `bugfix-parity`
   - What WEB does: parses/fetches the ICS through the message's source client and owner account, including directly viewed shared folders (`components/email/calendar-invitation-banner.tsx:373-388`, `412-432`; changelog 1.9.0).
   - What RN does: `parseCalendarBlob(attachment.blobId)` uses `jmapClient.accountId` (`src/components/email/CalendarInvitationBanner.tsx:54`, `src/api/calendar.ts:355-360`) even though `EmailPane` knows `jmapAccountId`; Stalwart answers `CalendarEvent/parse` with an error for a blob in another account, so invitations in group/shared mailboxes show nothing (state `error` → banner hidden).
   - Fix hint: pass `jmapAccountId` from `EmailPane` into the banner and through to `parseCalendarBlob(blobId, accountId)`.
@@ -150,7 +150,7 @@ RN has a solid single-message reader (WebView body with CSP, shrink-to-fit + pin
 
 ### Attachments
 
-- [ ] **Forwarding drops every attachment** — `P1` — `bug`
+- [x] **Forwarding drops every attachment — fixed in 7f956d6** — `P1` — `bug`
   - What WEB does: forward pre-populates the composer with the original's attachments by blobId (minus embedded cid images) (`components/email/email-composer.tsx:598-616`, #543).
   - What RN does: `navigateCompose('forward')` passes only from/to/cc/subject/plain body (`src/screens/EmailThreadScreen.tsx:366-382`); the `Compose.replyTo` param has no `attachments` field (`src/navigation/types.ts:7-19`) and `ComposeScreen` never seeds `attachments` from the original (`src/screens/ComposeScreen.tsx:354`). A forwarded invoice arrives without the PDF.
   - Fix hint: add `attachments?: Attachment[]` to the route param, and in `ComposeScreen` initialise `attachments` with `{blobId,name,type,size}` entries (blobs are account-scoped so no re-upload is needed; for shared-folder messages the blob belongs to the owner account — either re-upload via `getDownloadUrl(..., ownerAccountId)` + `uploadBytes`, or block forward there).
@@ -187,17 +187,17 @@ RN has a solid single-message reader (WebView body with CSP, shrink-to-fit + pin
 
 ### Actions from the viewer
 
-- [ ] **`In-Reply-To`/`References` are written with the JMAP email id (#234 bugfix-parity)** — `P1` — `bug`
+- [x] **`In-Reply-To`/`References` are written with the JMAP email id (#234 bugfix-parity) — fixed in 7f956d6** — `P1` — `bug`
   - What WEB does: passes the original's RFC `messageId` and `references`, stripped of brackets, as JMAP `inReplyTo`/`references` arrays (`lib/jmap/client.ts:3124-3194`; changelog 1.5.4 #234).
   - What RN does: `navigateCompose` sets `inReplyTo: email.id` (`src/screens/EmailThreadScreen.tsx:379`), and `sendEmail` writes it verbatim into `header:In-Reply-To:asText` / `header:References:asText` (`src/api/email.ts:823-826`). The outgoing header is a bare Stalwart object id, not a msg-id, so recipients' clients cannot thread the reply and `References` is never accumulated. `messageId`/`references` are not even fetched (see headers finding).
   - Fix hint: fetch `messageId`/`references`, pass `inReplyTo: email.messageId?.[0]` and `references: [...(email.references ?? []), email.messageId[0]]`, and send them as JMAP `inReplyTo`/`references` arrays (or `<…>`-wrapped `header:…:asMessageIds`).
 
-- [ ] **Reply addressing: Reply-To ignored, own addresses kept on reply-all, self-sent thread replies (#703), external Reply-To on self-sent (1.9.0)** — `P1` — `bugfix-parity`
+- [x] **Reply addressing: Reply-To ignored, own addresses kept on reply-all, self-sent thread replies (#703), external Reply-To on self-sent (1.9.0) — fixed in 7f956d6** — `P1` — `bugfix-parity`
   - What WEB does: `buildReplyRecipients` — reply goes to `Reply-To` if present else `From`; reply-all adds original To/CC minus the user's own identities (exact and `+tag`-stripped); replying to your own message continues to its original recipients; an external Reply-To on a self-sent message still wins (`lib/reply-recipients.ts:74-111`, `components/mail/mail-app.tsx:920`, `2940-2944`).
   - What RN does: `initialTo` = From (+ all original To on reply-all, including the user's own address), `initialCc` = all CC; `email.replyTo` is fetched but never passed (`src/screens/ComposeScreen.tsx:299-319`, `src/screens/EmailThreadScreen.tsx:366-382`). Replying to a newsletter with `Reply-To: support@…` mails the no-reply sender; reply-all sends the user a copy; replying to your own sent message addresses yourself.
   - Fix hint: copy `lib/reply-recipients.ts` (pure), pass `replyToAddresses: email.replyTo` in the route param and the identities' emails as `ownEmails`.
 
-- [ ] **Reply/forward quote is plain text only — HTML formatting and inline images lost (#163, #543)** — `P2` — `bugfix-parity`
+- [x] **Reply/forward quote is plain text only — HTML formatting and inline images lost (#163, #543) — fixed in 7f956d6** — `P2` — `bugfix-parity`
   - What WEB does: quotes the sanitized HTML body (with cid images re-attached inline) inside an editable quote island, localized "On … wrote:" header with `Name <email>` (`components/email/email-composer.tsx:462-500`, `lib/quote-header.ts:54-91`; changelog 1.7.1, 1.7.3, 1.8.1).
   - What RN does: `buildInitialHtml` supports `htmlBody` (`src/lib/compose-html.ts:79-83`) but the viewer only passes `body: plainTextBody(email)` (`src/screens/EmailThreadScreen.tsx:377`), and the header uses display name only (`compose-html.ts:31-35`) rather than WEB's `Name <email>` (#482).
   - Fix hint: pass `htmlBody` (sanitized via `stripDangerousTags`, cid refs rewritten to fetched data URIs or re-attached with the same `cid`) and switch `senderName` to the `Name <email>` form.
@@ -207,7 +207,7 @@ RN has a solid single-message reader (WebView body with CSP, shrink-to-fit + pin
   - What RN does: none.
   - Fix hint: add a More-sheet entry that opens `Compose` with `attachments: [{blobId: email.blobId, name, type: 'message/rfc822', size: email.size}]` (depends on the forward-attachments fix).
 
-- [ ] **Reply identity selection: exact match only, no `+tag` or catch-all domain override (#246)** — `P3` — `partial`
+- [x] **Reply identity selection: exact match only, no `+tag` or catch-all domain override (#246) — fixed in 5b72c4d** — `P3` — `partial`
   - What WEB does: `resolveReplyFrom` — exact, then `+tag`-stripped, then same-domain catch-all with a From override (`lib/reply-identity.ts:197-256`).
   - What RN does: `identities.find(i => i.email === candidate.email)` (`src/screens/ComposeScreen.tsx:431-437`).
   - Fix hint: port `resolveReplyFrom`; the override needs a From override in `sendEmail`.
@@ -229,7 +229,7 @@ RN has a solid single-message reader (WebView body with CSP, shrink-to-fit + pin
 
 ### Trusted senders / settings
 
-- [ ] **"Trust sender" writes to the Trusted Senders address book even when the setting is off** — `P3` — `rn-only-bug`
+- [x] **"Trust sender" writes to the Trusted Senders address book even when the setting is off — fixed in 06742ef** — `P3` — `rn-only-bug`
   - What WEB does: writes to the book only when `trustedSendersAddressBook` is on, else to the local list (`components/email/email-viewer.tsx:4646-4655`, `components/trusted-senders-modal.tsx:136-140`).
   - What RN does: always does both (`src/components/EmailBodyView.tsx:644-653`), and `addToTrustedSendersBook` creates the book on first add (`src/stores/contacts-store.ts:308-321`), so a user who left the setting off (default `false`, `src/stores/settings-store.ts:239`) still gets a server-side "Trusted Senders" address book; the settings modal then lists only the local entries (`src/components/settings/ContentSendersSettings.tsx:19-21`, `123-144`), so book-trusted senders are invisible/unremovable there.
   - Fix hint: gate the book write on the setting (or, matching WEB 1.9.0, default the setting to on for contacts-capable accounts) and show `trustedSenderEmails` in the settings modal with remove support.
diff --git a/package-lock.json b/package-lock.json
index 88b3bef8..0b2e4ab7 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -27,6 +27,7 @@
         "expo-image-picker": "~17.0.10",
         "expo-intent-launcher": "~13.0.8",
         "expo-localization": "~17.0.8",
+        "expo-notifications": "^0.32.17",
         "expo-secure-store": "~15.0.8",
         "expo-sharing": "~14.0.8",
         "expo-status-bar": "~3.0.9",
@@ -2390,6 +2391,12 @@
         "node": ">=8"
       }
     },
+    "node_modules/@ide/backoff": {
+      "version": "1.0.0",
+      "resolved": "https://registry.npmjs.org/@ide/backoff/-/backoff-1.0.0.tgz",
+      "integrity": "sha512-F0YfUDjvT+Mtt/R4xdl2X0EYCHMMiJqNLdxHD++jDT5ydEFIyqbCHh51Qx2E211dgZprPKhV7sHmnXKpLuvc5g==",
+      "license": "MIT"
+    },
     "node_modules/@isaacs/fs-minipass": {
       "version": "4.0.1",
       "resolved": "https://registry.npmjs.org/@isaacs/fs-minipass/-/fs-minipass-4.0.1.tgz",
@@ -3935,6 +3942,19 @@
       "integrity": "sha512-BSHWgDSAiKs50o2Re8ppvp3seVHXSRM44cdSsT9FfNEUUZLOGWVCsiWaRPWM1Znn+mqZ1OfVZ3z3DWEzSp7hRA==",
       "license": "MIT"
     },
+    "node_modules/assert": {
+      "version": "2.1.0",
+      "resolved": "https://registry.npmjs.org/assert/-/assert-2.1.0.tgz",
+      "integrity": "sha512-eLHpSK/Y4nhMJ07gDaAzoX/XAKS8PSaojml3M0DM4JpV1LAi5JOJ/p6H/XWrl8L+DzVEvVCW1z3vWAaB9oTsQw==",
+      "license": "MIT",
+      "dependencies": {
+        "call-bind": "^1.0.2",
+        "is-nan": "^1.3.2",
+        "object-is": "^1.1.5",
+        "object.assign": "^4.1.4",
+        "util": "^0.12.5"
+      }
+    },
     "node_modules/assertion-error": {
       "version": "2.0.1",
       "resolved": "https://registry.npmjs.org/assertion-error/-/assertion-error-2.0.1.tgz",
@@ -3951,6 +3971,21 @@
       "integrity": "sha512-csOlWGAcRFJaI6m+F2WKdnMKr4HhdhFVBk0H/QbJFMCr+uO2kwohwXQPxw/9OCxp05r5ghVBFSyioixx3gfkNQ==",
       "license": "MIT"
     },
+    "node_modules/available-typed-arrays": {
+      "version": "1.0.7",
+      "resolved": "https://registry.npmjs.org/available-typed-arrays/-/available-typed-arrays-1.0.7.tgz",
+      "integrity": "sha512-wvUjBtSGN7+7SjNpq/9M2Tg350UZD3q62IFZLbRAR1bSMlCo1ZaeW+BJ+D090e4hIIZLBcTDWe4Mh4jvUDajzQ==",
+      "license": "MIT",
+      "dependencies": {
+        "possible-typed-array-names": "^1.0.0"
+      },
+      "engines": {
+        "node": ">= 0.4"
+      },
+      "funding": {
+        "url": "https://github.com/sponsors/ljharb"
+      }
+    },
     "node_modules/babel-jest": {
       "version": "29.7.0",
       "resolved": "https://registry.npmjs.org/babel-jest/-/babel-jest-29.7.0.tgz",
@@ -4211,6 +4246,12 @@
         "@babel/core": "^7.0.0"
       }
     },
+    "node_modules/badgin": {
+      "version": "1.2.3",
+      "resolved": "https://registry.npmjs.org/badgin/-/badgin-1.2.3.tgz",
+      "integrity": "sha512-NQGA7LcfCpSzIbGRbkgjgdWkjy7HI+Th5VLxTJfW5EeaAf3fnS+xWQaQOCYiny+q6QSvxqoSO04vCx+4u++EJw==",
+      "license": "MIT"
+    },
     "node_modules/balanced-match": {
       "version": "1.0.2",
       "resolved": "https://registry.npmjs.org/balanced-match/-/balanced-match-1.0.2.tgz",
@@ -4416,6 +4457,53 @@
         "node": ">= 0.8"
       }
     },
+    "node_modules/call-bind": {
+      "version": "1.0.9",
+      "resolved": "https://registry.npmjs.org/call-bind/-/call-bind-1.0.9.tgz",
+      "integrity": "sha512-a/hy+pNsFUTR+Iz8TCJvXudKVLAnz/DyeSUo10I5yvFDQJBFU2s9uqQpoSrJlroHUKoKqzg+epxyP9lqFdzfBQ==",
+      "license": "MIT",
+      "dependencies": {
+        "call-bind-apply-helpers": "^1.0.2",
+        "es-define-property": "^1.0.1",
+        "get-intrinsic": "^1.3.0",
+        "set-function-length": "^1.2.2"
+      },
+      "engines": {
+        "node": ">= 0.4"
+      },
+      "funding": {
+        "url": "https://github.com/sponsors/ljharb"
+      }
+    },
+    "node_modules/call-bind-apply-helpers": {
+      "version": "1.0.2",
+      "resolved": "https://registry.npmjs.org/call-bind-apply-helpers/-/call-bind-apply-helpers-1.0.2.tgz",
+      "integrity": "sha512-Sp1ablJ0ivDkSzjcaJdxEunN5/XvksFJ2sMBFfq6x0ryhQV/2b/KwFe21cMpmHtPOSij8K99/wSfoEuTObmuMQ==",
+      "license": "MIT",
+      "dependencies": {
+        "es-errors": "^1.3.0",
+        "function-bind": "^1.1.2"
+      },
+      "engines": {
+        "node": ">= 0.4"
+      }
+    },
+    "node_modules/call-bound": {
+      "version": "1.0.4",
+      "resolved": "https://registry.npmjs.org/call-bound/-/call-bound-1.0.4.tgz",
+      "integrity": "sha512-+ys997U96po4Kx/ABpBCqhA9EuxJaQWDQg7295H4hBphv3IZg0boBKuwYpt4YXp6MZ5AmZQnU/tyMTlRpaSejg==",
+      "license": "MIT",
+      "dependencies": {
+        "call-bind-apply-helpers": "^1.0.2",
+        "get-intrinsic": "^1.3.0"
+      },
+      "engines": {
+        "node": ">= 0.4"
+      },
+      "funding": {
+        "url": "https://github.com/sponsors/ljharb"
+      }
+    },
     "node_modules/camelcase": {
       "version": "6.3.0",
       "resolved": "https://registry.npmjs.org/camelcase/-/camelcase-6.3.0.tgz",
@@ -4907,6 +4995,23 @@
         "url": "https://github.com/sponsors/sindresorhus"
       }
     },
+    "node_modules/define-data-property": {
+      "version": "1.1.4",
+      "resolved": "https://registry.npmjs.org/define-data-property/-/define-data-property-1.1.4.tgz",
+      "integrity": "sha512-rBMvIzlpA8v6E+SJZoo++HAYqsLrkg7MSfIinMPFhmkorw7X+dOXVJQs+QT69zGkzMyfDnIMN2Wid1+NbL3T+A==",
+      "license": "MIT",
+      "dependencies": {
+        "es-define-property": "^1.0.0",
+        "es-errors": "^1.3.0",
+        "gopd": "^1.0.1"
+      },
+      "engines": {
+        "node": ">= 0.4"
+      },
+      "funding": {
+        "url": "https://github.com/sponsors/ljharb"
+      }
+    },
     "node_modules/define-lazy-prop": {
       "version": "2.0.0",
       "resolved": "https://registry.npmjs.org/define-lazy-prop/-/define-lazy-prop-2.0.0.tgz",
@@ -4916,6 +5021,23 @@
         "node": ">=8"
       }
     },
+    "node_modules/define-properties": {
+      "version": "1.2.1",
+      "resolved": "https://registry.npmjs.org/define-properties/-/define-properties-1.2.1.tgz",
+      "integrity": "sha512-8QmQKqEASLd5nx0U1B1okLElbUuuttJ/AnYmRXbbbGDWh6uS208EjD4Xqq/I9wK7u0v6O08XhTWnt5XtEbR6Dg==",
+      "license": "MIT",
+      "dependencies": {
+        "define-data-property": "^1.0.1",
+        "has-property-descriptors": "^1.0.0",
+        "object-keys": "^1.1.1"
+      },
+      "engines": {
+        "node": ">= 0.4"
+      },
+      "funding": {
+        "url": "https://github.com/sponsors/ljharb"
+      }
+    },
     "node_modules/depd": {
       "version": "2.0.0",
       "resolved": "https://registry.npmjs.org/depd/-/depd-2.0.0.tgz",
@@ -5026,6 +5148,20 @@
         "url": "https://dotenvx.com"
       }
     },
+    "node_modules/dunder-proto": {
+      "version": "1.0.1",
+      "resolved": "https://registry.npmjs.org/dunder-proto/-/dunder-proto-1.0.1.tgz",
+      "integrity": "sha512-KIN/nDJBQRcXw0MLVhZE9iQHmG68qAVIBg9CqmUYjmQIhgij9U5MFvrqkUL5FbtyyzZuOeOt0zdeRe4UY7ct+A==",
+      "license": "MIT",
+      "dependencies": {
+        "call-bind-apply-helpers": "^1.0.1",
+        "es-errors": "^1.3.0",
+        "gopd": "^1.2.0"
+      },
+      "engines": {
+        "node": ">= 0.4"
+      }
+    },
     "node_modules/ee-first": {
       "version": "1.1.1",
       "resolved": "https://registry.npmjs.org/ee-first/-/ee-first-1.1.1.tgz",
@@ -5083,6 +5219,24 @@
         "stackframe": "^1.3.4"
       }
     },
+    "node_modules/es-define-property": {
+      "version": "1.0.1",
+      "resolved": "https://registry.npmjs.org/es-define-property/-/es-define-property-1.0.1.tgz",
+      "integrity": "sha512-e3nRfgfUZ4rNGL232gUgX06QNyyez04KdjFrF+LTRoOXmrOgFKDg4BCdsjW8EnT69eqdYGmRpJwiPVYNrCaW3g==",
+      "license": "MIT",
+      "engines": {
+        "node": ">= 0.4"
+      }
+    },
+    "node_modules/es-errors": {
+      "version": "1.3.0",
+      "resolved": "https://registry.npmjs.org/es-errors/-/es-errors-1.3.0.tgz",
+      "integrity": "sha512-Zf5H2Kxt2xjTvbJvP2ZWLEICxA6j+hAmMzIlypy4xcBg1vKVnx89Wy0GbS+kf5cwCVFFzdCFh2XSCFNULS6csw==",
+      "license": "MIT",
+      "engines": {
+        "node": ">= 0.4"
+      }
+    },
     "node_modules/es-module-lexer": {
       "version": "2.0.0",
       "resolved": "https://registry.npmjs.org/es-module-lexer/-/es-module-lexer-2.0.0.tgz",
@@ -5090,6 +5244,18 @@
       "dev": true,
       "license": "MIT"
     },
+    "node_modules/es-object-atoms": {
+      "version": "1.1.2",
+      "resolved": "https://registry.npmjs.org/es-object-atoms/-/es-object-atoms-1.1.2.tgz",
+      "integrity": "sha512-HWcBoN6NileqtSydK2FqHbS/LoDd2pqrnQHLyJzBj4kOp/ky2MWMN694xOfkK8/SnUsW2DH7EfyVlydKCsm1Zw==",
+      "license": "MIT",
+      "dependencies": {
+        "es-errors": "^1.3.0"
+      },
+      "engines": {
+        "node": ">= 0.4"
+      }
+    },
     "node_modules/escalade": {
       "version": "3.2.0",
       "resolved": "https://registry.npmjs.org/escalade/-/escalade-3.2.0.tgz",
@@ -5217,6 +5383,15 @@
         }
       }
     },
+    "node_modules/expo-application": {
+      "version": "7.0.8",
+      "resolved": "https://registry.npmjs.org/expo-application/-/expo-application-7.0.8.tgz",
+      "integrity": "sha512-qFGyxk7VJbrNOQWBbE09XUuGuvkOgFS9QfToaK2FdagM2aQ+x3CvGV2DuVgl/l4ZxPgIf3b/MNh9xHpwSwn74Q==",
+      "license": "MIT",
+      "peerDependencies": {
+        "expo": "*"
+      }
+    },
     "node_modules/expo-camera": {
       "version": "17.0.10",
       "resolved": "https://registry.npmjs.org/expo-camera/-/expo-camera-17.0.10.tgz",
@@ -5456,6 +5631,26 @@
         "react-native": "*"
       }
     },
+    "node_modules/expo-notifications": {
+      "version": "0.32.17",
+      "resolved": "https://registry.npmjs.org/expo-notifications/-/expo-notifications-0.32.17.tgz",
+      "integrity": "sha512-lwwzn7tImuzTzn9PAglZlS2VfZEvsfFGJTK9Eb8I4cqkGh2DI23YJFJH+WPEIu4QhDvk5JeBjklenJ8IZbmA4A==",
+      "license": "MIT",
+      "dependencies": {
+        "@expo/image-utils": "^0.8.8",
+        "@ide/backoff": "^1.0.0",
+        "abort-controller": "^3.0.0",
+        "assert": "^2.0.0",
+        "badgin": "^1.1.5",
+        "expo-application": "~7.0.8",
+        "expo-constants": "~18.0.13"
+      },
+      "peerDependencies": {
+        "expo": "*",
+        "react": "*",
+        "react-native": "*"
+      }
+    },
     "node_modules/expo-secure-store": {
       "version": "15.0.8",
       "resolved": "https://registry.npmjs.org/expo-secure-store/-/expo-secure-store-15.0.8.tgz",
@@ -5997,6 +6192,21 @@
       "integrity": "sha512-6FPvD/IVyT4ZlNe7Wcn5Fb/4ChigpucKYSvD6a+0iMoLn2inpo711eyIcKjmDtE5XNcgAkSH9uN/nfAeZzHEfg==",
       "license": "BSD-2-Clause"
     },
+    "node_modules/for-each": {
+      "version": "0.3.5",
+      "resolved": "https://registry.npmjs.org/for-each/-/for-each-0.3.5.tgz",
+      "integrity": "sha512-dKx12eRCVIzqCxFGplyFKJMPvLEWgmNtUrpTiJIR5u97zEhRG8ySrtboPHZXx7daLxQVrl643cTzbab2tkQjxg==",
+      "license": "MIT",
+      "dependencies": {
+        "is-callable": "^1.2.7"
+      },
+      "engines": {
+        "node": ">= 0.4"
+      },
+      "funding": {
+        "url": "https://github.com/sponsors/ljharb"
+      }
+    },
     "node_modules/freeport-async": {
       "version": "2.0.0",
       "resolved": "https://registry.npmjs.org/freeport-async/-/freeport-async-2.0.0.tgz",
@@ -6044,6 +6254,15 @@
         "url": "https://github.com/sponsors/ljharb"
       }
     },
+    "node_modules/generator-function": {
+      "version": "2.0.1",
+      "resolved": "https://registry.npmjs.org/generator-function/-/generator-function-2.0.1.tgz",
+      "integrity": "sha512-SFdFmIJi+ybC0vjlHN0ZGVGHc3lgE0DxPAT0djjVg+kjOnSqclqmj0KQ7ykTOLP6YxoqOvuAODGdcHJn+43q3g==",
+      "license": "MIT",
+      "engines": {
+        "node": ">= 0.4"
+      }
+    },
     "node_modules/gensync": {
       "version": "1.0.0-beta.2",
       "resolved": "https://registry.npmjs.org/gensync/-/gensync-1.0.0-beta.2.tgz",
@@ -6062,6 +6281,30 @@
         "node": "6.* || 8.* || >= 10.*"
       }
     },
+    "node_modules/get-intrinsic": {
+      "version": "1.3.0",
+      "resolved": "https://registry.npmjs.org/get-intrinsic/-/get-intrinsic-1.3.0.tgz",
+      "integrity": "sha512-9fSjSaos/fRIVIp+xSJlE6lfwhES7LNtKaCBIamHsjr2na1BiABJPo0mOjjz8GJDURarmCPGqaiVg5mfjb98CQ==",
+      "license": "MIT",
+      "dependencies": {
+        "call-bind-apply-helpers": "^1.0.2",
+        "es-define-property": "^1.0.1",
+        "es-errors": "^1.3.0",
+        "es-object-atoms": "^1.1.1",
+        "function-bind": "^1.1.2",
+        "get-proto": "^1.0.1",
+        "gopd": "^1.2.0",
+        "has-symbols": "^1.1.0",
+        "hasown": "^2.0.2",
+        "math-intrinsics": "^1.1.0"
+      },
+      "engines": {
+        "node": ">= 0.4"
+      },
+      "funding": {
+        "url": "https://github.com/sponsors/ljharb"
+      }
+    },
     "node_modules/get-package-type": {
       "version": "0.1.0",
       "resolved": "https://registry.npmjs.org/get-package-type/-/get-package-type-0.1.0.tgz",
@@ -6071,6 +6314,19 @@
         "node": ">=8.0.0"
       }
     },
+    "node_modules/get-proto": {
+      "version": "1.0.1",
+      "resolved": "https://registry.npmjs.org/get-proto/-/get-proto-1.0.1.tgz",
+      "integrity": "sha512-sTSfBjoXBp89JvIKIefqw7U2CCebsc74kiY6awiGogKtoSGbgjYE/G/+l9sF3MWFPNc9IcoOC4ODfKHfxFmp0g==",
+      "license": "MIT",
+      "dependencies": {
+        "dunder-proto": "^1.0.1",
+        "es-object-atoms": "^1.0.0"
+      },
+      "engines": {
+        "node": ">= 0.4"
+      }
+    },
     "node_modules/getenv": {
       "version": "2.0.0",
       "resolved": "https://registry.npmjs.org/getenv/-/getenv-2.0.0.tgz",
@@ -6133,6 +6389,18 @@
         "url": "https://github.com/sponsors/isaacs"
       }
     },
+    "node_modules/gopd": {
+      "version": "1.2.0",
+      "resolved": "https://registry.npmjs.org/gopd/-/gopd-1.2.0.tgz",
+      "integrity": "sha512-ZUKRh6/kUFoAiTAtTYPZJ3hw9wNxx+BIBOijnlG9PnrJsCcSjs1wyyD6vJpaYtgnzDrKYRSqf3OO6Rfa93xsRg==",
+      "license": "MIT",
+      "engines": {
+        "node": ">= 0.4"
+      },
+      "funding": {
+        "url": "https://github.com/sponsors/ljharb"
+      }
+    },
     "node_modules/graceful-fs": {
       "version": "4.2.11",
       "resolved": "https://registry.npmjs.org/graceful-fs/-/graceful-fs-4.2.11.tgz",
@@ -6148,6 +6416,45 @@
         "node": ">=4"
       }
     },
+    "node_modules/has-property-descriptors": {
+      "version": "1.0.2",
+      "resolved": "https://registry.npmjs.org/has-property-descriptors/-/has-property-descriptors-1.0.2.tgz",
+      "integrity": "sha512-55JNKuIW+vq4Ke1BjOTjM2YctQIvCT7GFzHwmfZPGo5wnrgkid0YQtnAleFSqumZm4az3n2BS+erby5ipJdgrg==",
+      "license": "MIT",
+      "dependencies": {
+        "es-define-property": "^1.0.0"
+      },
+      "funding": {
+        "url": "https://github.com/sponsors/ljharb"
+      }
+    },
+    "node_modules/has-symbols": {
+      "version": "1.1.0",
+      "resolved": "https://registry.npmjs.org/has-symbols/-/has-symbols-1.1.0.tgz",
+      "integrity": "sha512-1cDNdwJ2Jaohmb3sg4OmKaMBwuC48sYni5HUw2DvsC8LjGTLK9h+eb1X6RyuOHe4hT0ULCW68iomhjUoKUqlPQ==",
+      "license": "MIT",
+      "engines": {
+        "node": ">= 0.4"
+      },
+      "funding": {
+        "url": "https://github.com/sponsors/ljharb"
+      }
+    },
+    "node_modules/has-tostringtag": {
+      "version": "1.0.2",
+      "resolved": "https://registry.npmjs.org/has-tostringtag/-/has-tostringtag-1.0.2.tgz",
+      "integrity": "sha512-NqADB8VjPFLM2V0VvHUewwwsw0ZWBaIdgo+ieHtK3hasLz4qeCRjYcqfB6AQrBggRKppKF8L52/VqdVsO47Dlw==",
+      "license": "MIT",
+      "dependencies": {
+        "has-symbols": "^1.0.3"
+      },
+      "engines": {
+        "node": ">= 0.4"
+      },
+      "funding": {
+        "url": "https://github.com/sponsors/ljharb"
+      }
+    },
     "node_modules/hasown": {
       "version": "2.0.2",
       "resolved": "https://registry.npmjs.org/hasown/-/hasown-2.0.2.tgz",
@@ -6326,12 +6633,40 @@
         "loose-envify": "^1.0.0"
       }
     },
+    "node_modules/is-arguments": {
+      "version": "1.2.0",
+      "resolved": "https://registry.npmjs.org/is-arguments/-/is-arguments-1.2.0.tgz",
+      "integrity": "sha512-7bVbi0huj/wrIAOzb8U1aszg9kdi3KN/CyU19CTI7tAoZYEZoL9yCDXpbXN+uPsuWnP02cyug1gleqq+TU+YCA==",
+      "license": "MIT",
+      "dependencies": {
+        "call-bound": "^1.0.2",
+        "has-tostringtag": "^1.0.2"
+      },
+      "engines": {
+        "node": ">= 0.4"
+      },
+      "funding": {
+        "url": "https://github.com/sponsors/ljharb"
+      }
+    },
     "node_modules/is-arrayish": {
       "version": "0.3.4",
       "resolved": "https://registry.npmjs.org/is-arrayish/-/is-arrayish-0.3.4.tgz",
       "integrity": "sha512-m6UrgzFVUYawGBh1dUsWR5M2Clqic9RVXC/9f8ceNlv2IcO9j9J/z8UoCLPqtsPBFNzEpfR3xftohbfqDx8EQA==",
       "license": "MIT"
     },
+    "node_modules/is-callable": {
+      "version": "1.2.7",
+      "resolved": "https://registry.npmjs.org/is-callable/-/is-callable-1.2.7.tgz",
+      "integrity": "sha512-1BC0BVFhS/p0qtw6enp8e+8OD0UrK0oFLztSjNzhcKA3WDuJxxAPXzPuPtKkjEY9UUoEWlX/8fgKeu2S8i9JTA==",
+      "license": "MIT",
+      "engines": {
+        "node": ">= 0.4"
+      },
+      "funding": {
+        "url": "https://github.com/sponsors/ljharb"
+      }
+    },
     "node_modules/is-core-module": {
       "version": "2.16.1",
       "resolved": "https://registry.npmjs.org/is-core-module/-/is-core-module-2.16.1.tgz",
@@ -6371,6 +6706,41 @@
         "node": ">=8"
       }
     },
+    "node_modules/is-generator-function": {
+      "version": "1.1.2",
+      "resolved": "https://registry.npmjs.org/is-generator-function/-/is-generator-function-1.1.2.tgz",
+      "integrity": "sha512-upqt1SkGkODW9tsGNG5mtXTXtECizwtS2kA161M+gJPc1xdb/Ax629af6YrTwcOeQHbewrPNlE5Dx7kzvXTizA==",
+      "license": "MIT",
+      "dependencies": {
+        "call-bound": "^1.0.4",
+        "generator-function": "^2.0.0",
+        "get-proto": "^1.0.1",
+        "has-tostringtag": "^1.0.2",
+        "safe-regex-test": "^1.1.0"
+      },
+      "engines": {
+        "node": ">= 0.4"
+      },
+      "funding": {
+        "url": "https://github.com/sponsors/ljharb"
+      }
+    },
+    "node_modules/is-nan": {
+      "version": "1.3.2",
+      "resolved": "https://registry.npmjs.org/is-nan/-/is-nan-1.3.2.tgz",
+      "integrity": "sha512-E+zBKpQ2t6MEo1VsonYmluk9NxGrbzpeeLC2xIViuO2EjU2xsXsBPwTr3Ykv9l08UYEVEdWeRZNouaZqF6RN0w==",
+      "license": "MIT",
+      "dependencies": {
+        "call-bind": "^1.0.0",
+        "define-properties": "^1.1.3"
+      },
+      "engines": {
+        "node": ">= 0.4"
+      },
+      "funding": {
+        "url": "https://github.com/sponsors/ljharb"
+      }
+    },
     "node_modules/is-number": {
       "version": "7.0.0",
       "resolved": "https://registry.npmjs.org/is-number/-/is-number-7.0.0.tgz",
@@ -6389,6 +6759,39 @@
         "node": ">=8"
       }
     },
+    "node_modules/is-regex": {
+      "version": "1.2.1",
+      "resolved": "https://registry.npmjs.org/is-regex/-/is-regex-1.2.1.tgz",
+      "integrity": "sha512-MjYsKHO5O7mCsmRGxWcLWheFqN9DJ/2TmngvjKXihe6efViPqc274+Fx/4fYj/r03+ESvBdTXK0V6tA3rgez1g==",
+      "license": "MIT",
+      "dependencies": {
+        "call-bound": "^1.0.2",
+        "gopd": "^1.2.0",
+        "has-tostringtag": "^1.0.2",
+        "hasown": "^2.0.2"
+      },
+      "engines": {
+        "node": ">= 0.4"
+      },
+      "funding": {
+        "url": "https://github.com/sponsors/ljharb"
+      }
+    },
+    "node_modules/is-typed-array": {
+      "version": "1.1.15",
+      "resolved": "https://registry.npmjs.org/is-typed-array/-/is-typed-array-1.1.15.tgz",
+      "integrity": "sha512-p3EcsicXjit7SaskXHs1hA91QxgTw46Fv6EFKKGS5DRFLD8yKnohjF3hxoju94b/OcMZoQukzpPpBE9uLVKzgQ==",
+      "license": "MIT",
+      "dependencies": {
+        "which-typed-array": "^1.1.16"
+      },
+      "engines": {
+        "node": ">= 0.4"
+      },
+      "funding": {
+        "url": "https://github.com/sponsors/ljharb"
+      }
+    },
     "node_modules/is-wsl": {
       "version": "2.2.0",
       "resolved": "https://registry.npmjs.org/is-wsl/-/is-wsl-2.2.0.tgz",
@@ -7329,6 +7732,15 @@
       "integrity": "sha512-ocnPZQLNpvbedwTy9kNrQEsknEfgvcLMvOtz3sFeWApDq1MXH1TqkCIx58xlpESsfwQOnuBO9beyQuNGzVvuhQ==",
       "license": "Apache-2.0"
     },
+    "node_modules/math-intrinsics": {
+      "version": "1.1.0",
+      "resolved": "https://registry.npmjs.org/math-intrinsics/-/math-intrinsics-1.1.0.tgz",
+      "integrity": "sha512-/IXtbwEk5HTPyEwyKX6hGkYXxM9nbj64B+ilVJnC/R6B0pH5G4V3b0pVbL7DBj4tkhBAppbQUlf6F6Xl9LHu1g==",
+      "license": "MIT",
+      "engines": {
+        "node": ">= 0.4"
+      }
+    },
     "node_modules/mdn-data": {
       "version": "2.0.14",
       "resolved": "https://registry.npmjs.org/mdn-data/-/mdn-data-2.0.14.tgz",
@@ -7958,6 +8370,51 @@
         "node": ">=0.10.0"
       }
     },
+    "node_modules/object-is": {
+      "version": "1.1.6",
+      "resolved": "https://registry.npmjs.org/object-is/-/object-is-1.1.6.tgz",
+      "integrity": "sha512-F8cZ+KfGlSGi09lJT7/Nd6KJZ9ygtvYC0/UYYLI9nmQKLMnydpB9yvbv9K1uSkEu7FU9vYPmVwLg328tX+ot3Q==",
+      "license": "MIT",
+      "dependencies": {
+        "call-bind": "^1.0.7",
+        "define-properties": "^1.2.1"
+      },
+      "engines": {
+        "node": ">= 0.4"
+      },
+      "funding": {
+        "url": "https://github.com/sponsors/ljharb"
+      }
+    },
+    "node_modules/object-keys": {
+      "version": "1.1.1",
+      "resolved": "https://registry.npmjs.org/object-keys/-/object-keys-1.1.1.tgz",
+      "integrity": "sha512-NuAESUOUMrlIXOfHKzD6bpPu3tYt3xvjNdRIQ+FeT0lNb4K8WR70CaDxhuNguS2XG+GjkyMwOzsN5ZktImfhLA==",
+      "license": "MIT",
+      "engines": {
+        "node": ">= 0.4"
+      }
+    },
+    "node_modules/object.assign": {
+      "version": "4.1.7",
+      "resolved": "https://registry.npmjs.org/object.assign/-/object.assign-4.1.7.tgz",
+      "integrity": "sha512-nK28WOo+QIjBkDduTINE4JkF/UJJKyf2EJxvJKfblDpyg0Q+pkOHNTL0Qwy6NP6FhE/EnzV73BxxqcJaXY9anw==",
+      "license": "MIT",
+      "dependencies": {
+        "call-bind": "^1.0.8",
+        "call-bound": "^1.0.3",
+        "define-properties": "^1.2.1",
+        "es-object-atoms": "^1.0.0",
+        "has-symbols": "^1.1.0",
+        "object-keys": "^1.1.1"
+      },
+      "engines": {
+        "node": ">= 0.4"
+      },
+      "funding": {
+        "url": "https://github.com/sponsors/ljharb"
+      }
+    },
     "node_modules/obug": {
       "version": "2.1.1",
       "resolved": "https://registry.npmjs.org/obug/-/obug-2.1.1.tgz",
@@ -8258,6 +8715,15 @@
         "node": ">=4.0.0"
       }
     },
+    "node_modules/possible-typed-array-names": {
+      "version": "1.1.0",
+      "resolved": "https://registry.npmjs.org/possible-typed-array-names/-/possible-typed-array-names-1.1.0.tgz",
+      "integrity": "sha512-/+5VFTchJDoVj3bhoqi6UeymcD00DAwb1nJwamzPvHEszJ4FpF6SNNbUbOS8yI56qHzdV8eK0qEfOSiodkTdxg==",
+      "license": "MIT",
+      "engines": {
+        "node": ">= 0.4"
+      }
+    },
     "node_modules/postal-mime": {
       "version": "3.0.0",
       "resolved": "https://registry.npmjs.org/postal-mime/-/postal-mime-3.0.0.tgz",
@@ -9009,6 +9475,23 @@
       ],
       "license": "MIT"
     },
+    "node_modules/safe-regex-test": {
+      "version": "1.1.0",
+      "resolved": "https://registry.npmjs.org/safe-regex-test/-/safe-regex-test-1.1.0.tgz",
+      "integrity": "sha512-x/+Cz4YrimQxQccJf5mKEbIa1NzeCRNI5Ecl/ekmlYaampdNLPalVyIcCZNNH3MvmqBugV5TMYZXv0ljslUlaw==",
+      "license": "MIT",
+      "dependencies": {
+        "call-bound": "^1.0.2",
+        "es-errors": "^1.3.0",
+        "is-regex": "^1.2.1"
+      },
+      "engines": {
+        "node": ">= 0.4"
+      },
+      "funding": {
+        "url": "https://github.com/sponsors/ljharb"
+      }
+    },
     "node_modules/sax": {
       "version": "1.6.0",
       "resolved": "https://registry.npmjs.org/sax/-/sax-1.6.0.tgz",
@@ -9138,6 +9621,23 @@
         "node": ">= 0.8"
       }
     },
+    "node_modules/set-function-length": {
+      "version": "1.2.2",
+      "resolved": "https://registry.npmjs.org/set-function-length/-/set-function-length-1.2.2.tgz",
+      "integrity": "sha512-pgRc4hJ4/sNjWCSS9AmnS40x3bNMDTknHgL5UaMBTMyJnU90EgWh1Rz+MC9eFu4BuN/UwZjKQuY/1v3rM7HMfg==",
+      "license": "MIT",
+      "dependencies": {
+        "define-data-property": "^1.1.4",
+        "es-errors": "^1.3.0",
+        "function-bind": "^1.1.2",
+        "get-intrinsic": "^1.2.4",
+        "gopd": "^1.0.1",
+        "has-property-descriptors": "^1.0.2"
+      },
+      "engines": {
+        "node": ">= 0.4"
+      }
+    },
     "node_modules/setimmediate": {
       "version": "1.0.5",
       "resolved": "https://registry.npmjs.org/setimmediate/-/setimmediate-1.0.5.tgz",
@@ -9932,6 +10432,19 @@
         "react": "^16.8.0 || ^17.0.0 || ^18.0.0 || ^19.0.0"
       }
     },
+    "node_modules/util": {
+      "version": "0.12.5",
+      "resolved": "https://registry.npmjs.org/util/-/util-0.12.5.tgz",
+      "integrity": "sha512-kZf/K6hEIrWHI6XqOFUiiMa+79wE/D8Q+NCNAWclkyg3b4d2k7s0QGepNjiABc+aR3N1PAyHL7p6UcLY6LmrnA==",
+      "license": "MIT",
+      "dependencies": {
+        "inherits": "^2.0.3",
+        "is-arguments": "^1.0.4",
+        "is-generator-function": "^1.0.7",
+        "is-typed-array": "^1.1.3",
+        "which-typed-array": "^1.1.2"
+      }
+    },
     "node_modules/util-deprecate": {
       "version": "1.0.2",
       "resolved": "https://registry.npmjs.org/util-deprecate/-/util-deprecate-1.0.2.tgz",
@@ -10263,6 +10776,27 @@
         "node": ">= 8"
       }
     },
+    "node_modules/which-typed-array": {
+      "version": "1.1.22",
+      "resolved": "https://registry.npmjs.org/which-typed-array/-/which-typed-array-1.1.22.tgz",
+      "integrity": "sha512-fvO4ExWMFsqyhG3AiPAObMuY1lxaqgYcxbc49CNdWDDECOJNgQyvsOWVwbZc+qf3rzRtxojBK+CMEv0Ld5CYpw==",
+      "license": "MIT",
+      "dependencies": {
+        "available-typed-arrays": "^1.0.7",
+        "call-bind": "^1.0.9",
+        "call-bound": "^1.0.4",
+        "for-each": "^0.3.5",
+        "get-proto": "^1.0.1",
+        "gopd": "^1.2.0",
+        "has-tostringtag": "^1.0.2"
+      },
+      "engines": {
+        "node": ">= 0.4"
+      },
+      "funding": {
+        "url": "https://github.com/sponsors/ljharb"
+      }
+    },
     "node_modules/why-is-node-running": {
       "version": "2.3.0",
       "resolved": "https://registry.npmjs.org/why-is-node-running/-/why-is-node-running-2.3.0.tgz",
diff --git a/package.json b/package.json
index 87b87d73..ee4d87c7 100644
--- a/package.json
+++ b/package.json
@@ -35,6 +35,7 @@
     "expo-image-picker": "~17.0.10",
     "expo-intent-launcher": "~13.0.8",
     "expo-localization": "~17.0.8",
+    "expo-notifications": "^0.32.17",
     "expo-secure-store": "~15.0.8",
     "expo-sharing": "~14.0.8",
     "expo-status-bar": "~3.0.9",
diff --git a/src/components/email/ActionSheet.tsx b/src/components/email/ActionSheet.tsx
new file mode 100644
index 00000000..0001ae2c
--- /dev/null
+++ b/src/components/email/ActionSheet.tsx
@@ -0,0 +1,143 @@
+import React from 'react';
+import { View, Text, StyleSheet, Pressable, Modal, Animated, Easing } from 'react-native';
+import { useSafeAreaInsets } from 'react-native-safe-area-context';
+import { X } from 'lucide-react-native';
+import { spacing, radius, typography, type ThemePalette } from '../../theme/tokens';
+import { useColors } from '../../theme/colors';
+import { useSheetDrag } from '../../lib/use-sheet-drag';
+
+export interface ActionSheetItem {
+  key: string;
+  label: string;
+  icon?: React.ReactNode;
+  trailing?: React.ReactNode;
+  destructive?: boolean;
+  disabled?: boolean;
+  onPress: () => void;
+}
+
+interface ActionSheetProps {
+  visible: boolean;
+  title: string;
+  subtitle?: string;
+  items: ActionSheetItem[];
+  onClose: () => void;
+  children?: React.ReactNode;
+}
+
+/**
+ * Bottom sheet with a list of actions - the same slide-up/drag-to-dismiss
+ * pattern as the reader's More sheet, reused for address and attachment
+ * actions.
+ */
+export function ActionSheet({ visible, title, subtitle, items, onClose, children }: ActionSheetProps) {
+  const c = useColors();
+  const styles = React.useMemo(() => makeStyles(c), [c]);
+  const insets = useSafeAreaInsets();
+  const slideY = React.useRef(new Animated.Value(500)).current;
+  const overlayOpacity = React.useRef(new Animated.Value(0)).current;
+  const dragHandlers = useSheetDrag({ slideY, closedY: 500, onClose });
+
+  React.useEffect(() => {
+    if (visible) {
+      Animated.parallel([
+        Animated.timing(slideY, { toValue: 0, duration: 220, easing: Easing.out(Easing.cubic), useNativeDriver: true }),
+        Animated.timing(overlayOpacity, { toValue: 1, duration: 220, useNativeDriver: true }),
+      ]).start();
+    } else {
+      Animated.parallel([
+        Animated.timing(slideY, { toValue: 500, duration: 180, easing: Easing.in(Easing.cubic), useNativeDriver: true }),
+        Animated.timing(overlayOpacity, { toValue: 0, duration: 180, useNativeDriver: true }),
+      ]).start();
+    }
+  }, [visible, slideY, overlayOpacity]);
+
+  return (
+    <Modal visible={visible} transparent animationType="none" onRequestClose={onClose} statusBarTranslucent>
+      <Animated.View style={[styles.overlay, { opacity: overlayOpacity }]}>
+        <Pressable style={styles.overlayPress} onPress={onClose} />
+      </Animated.View>
+      <Animated.View
+        style={[
+          styles.sheet,
+          { paddingBottom: Math.max(insets.bottom, spacing.md), transform: [{ translateY: slideY }] },
+        ]}
+      >
+        <View {...dragHandlers}>
+          <View style={styles.handleHit}>
+            <View style={styles.handle} />
+          </View>
+          <View style={styles.header}>
+            <View style={styles.headerText}>
+              <Text style={styles.title} numberOfLines={1}>{title}</Text>
+              {subtitle ? <Text style={styles.subtitle} numberOfLines={1}>{subtitle}</Text> : null}
+            </View>
+            <Pressable onPress={onClose} hitSlop={8} style={styles.close}>
+              <X size={18} color={c.textSecondary} />
+            </Pressable>
+          </View>
+        </View>
+        {children}
+        {items.map((item) => (
+          <Pressable
+            key={item.key}
+            onPress={item.disabled ? undefined : item.onPress}
+            style={({ pressed }) => [styles.item, pressed && styles.itemPressed, item.disabled && styles.itemDisabled]}
+          >
+            <View style={styles.itemIcon}>{item.icon}</View>
+            <Text style={[styles.itemLabel, item.destructive && styles.itemLabelDestructive]}>{item.label}</Text>
+            {item.trailing}
+          </Pressable>
+        ))}
+      </Animated.View>
+    </Modal>
+  );
+}
+
+function makeStyles(c: ThemePalette) {
+  return StyleSheet.create({
+    overlay: { ...StyleSheet.absoluteFillObject, backgroundColor: 'rgba(0,0,0,0.5)' },
+    overlayPress: { flex: 1 },
+    sheet: {
+      position: 'absolute',
+      left: 0,
+      right: 0,
+      bottom: 0,
+      backgroundColor: c.popover,
+      borderTopLeftRadius: radius.lg,
+      borderTopRightRadius: radius.lg,
+      borderTopWidth: 1,
+      borderColor: c.border,
+      paddingTop: spacing.sm,
+    },
+    handleHit: { alignItems: 'center', paddingTop: spacing.xs, paddingBottom: spacing.sm },
+    handle: { width: 36, height: 4, borderRadius: 2, backgroundColor: c.border },
+    header: {
+      flexDirection: 'row',
+      alignItems: 'center',
+      justifyContent: 'space-between',
+      paddingHorizontal: spacing.lg,
+      paddingBottom: spacing.sm,
+      borderBottomWidth: 1,
+      borderBottomColor: c.border,
+      gap: spacing.sm,
+    },
+    headerText: { flex: 1, minWidth: 0 },
+    title: { ...typography.bodySemibold, color: c.text },
+    subtitle: { ...typography.caption, color: c.textMuted, marginTop: 2 },
+    close: { width: 28, height: 28, alignItems: 'center', justifyContent: 'center', borderRadius: radius.xs },
+    item: {
+      flexDirection: 'row',
+      alignItems: 'center',
+      gap: spacing.md,
+      paddingHorizontal: spacing.lg,
+      paddingVertical: spacing.md,
+      minHeight: 48,
+    },
+    itemPressed: { backgroundColor: c.surfaceHover },
+    itemDisabled: { opacity: 0.4 },
+    itemIcon: { width: 20, alignItems: 'center', justifyContent: 'center' },
+    itemLabel: { ...typography.body, color: c.text, flex: 1 },
+    itemLabelDestructive: { color: c.error },
+  });
+}
diff --git a/src/components/email/AddressActionSheet.tsx b/src/components/email/AddressActionSheet.tsx
new file mode 100644
index 00000000..8d6fea56
--- /dev/null
+++ b/src/components/email/AddressActionSheet.tsx
@@ -0,0 +1,85 @@
+import React from 'react';
+import { Alert } from 'react-native';
+import { useNavigation } from '@react-navigation/native';
+import type { NativeStackNavigationProp } from '@react-navigation/native-stack';
+import * as Clipboard from 'expo-clipboard';
+import { Copy, PenSquare, UserRound, UserRoundPlus } from 'lucide-react-native';
+import type { EmailAddress } from '../../api/types';
+import type { RootStackParamList } from '../../navigation/types';
+import { useContactsStore } from '../../stores/contacts-store';
+import { useLocaleStore } from '../../stores/locale-store';
+import { useColors } from '../../theme/colors';
+import { ActionSheet, type ActionSheetItem } from './ActionSheet';
+
+type Nav = NativeStackNavigationProp<RootStackParamList>;
+
+interface Props {
+  address: EmailAddress | null;
+  onClose: () => void;
+}
+
+/**
+ * Tap sheet for a sender/recipient: copy the address, start a message to it,
+ * open the matching contact or add one (the webmail's RecipientPopover).
+ */
+export function AddressActionSheet({ address, onClose }: Props) {
+  const c = useColors();
+  const t = useLocaleStore((s) => s.t);
+  const navigation = useNavigation<Nav>();
+  const findContactByEmail = useContactsStore((s) => s.findContactByEmail);
+
+  const email = address?.email ?? '';
+  const contact = React.useMemo(() => (email ? findContactByEmail(email) : undefined), [email, findContactByEmail]);
+
+  const items: ActionSheetItem[] = [
+    {
+      key: 'copy',
+      label: t('email_viewer.address_actions.copy', 'Copy address'),
+      icon: <Copy size={18} color={c.textSecondary} />,
+      onPress: () => {
+        onClose();
+        void Clipboard.setStringAsync(email).catch(() => {
+          Alert.alert(t('common.error', 'Error'), t('email_viewer.address_actions.copy_failed', 'Could not copy the address.'));
+        });
+      },
+    },
+    {
+      key: 'compose',
+      label: t('email_viewer.address_actions.compose', 'New message'),
+      icon: <PenSquare size={18} color={c.textSecondary} />,
+      onPress: () => {
+        onClose();
+        navigation.navigate('Compose', { prefillTo: [{ email, name: address?.name }] });
+      },
+    },
+    contact
+      ? {
+          key: 'contact',
+          label: t('email_viewer.view_contact', 'View contact'),
+          icon: <UserRound size={18} color={c.textSecondary} />,
+          onPress: () => {
+            onClose();
+            navigation.navigate('ContactDetail', { contactId: contact.id });
+          },
+        }
+      : {
+          key: 'add',
+          label: t('email_viewer.address_actions.add_contact', 'Add to contacts'),
+          icon: <UserRoundPlus size={18} color={c.textSecondary} />,
+          onPress: () => {
+            onClose();
+            navigation.navigate('ContactForm', { prefill: { email, name: address?.name } });
+          },
+        },
+  ];
+
+  return (
+    <ActionSheet
+      visible={!!address}
+      title={address?.name || email}
+      subtitle={address?.name ? email : undefined}
+      items={items}
+      onClose={onClose}
+    />
+  );
+}
diff --git a/src/components/email/AttachmentChips.tsx b/src/components/email/AttachmentChips.tsx
new file mode 100644
index 00000000..d2708f9a
--- /dev/null
+++ b/src/components/email/AttachmentChips.tsx
@@ -0,0 +1,311 @@
+import React from 'react';
+import { View, Text, StyleSheet, Pressable, ActivityIndicator, Alert } from 'react-native';
+import { Paperclip, Download, Eye, ExternalLink, Save, Share2, FolderArchive } from 'lucide-react-native';
+import type { Attachment, Email } from '../../api/types';
+import { spacing, radius, typography, type ThemePalette } from '../../theme/tokens';
+import { useColors } from '../../theme/colors';
+import { useSettingsStore } from '../../stores/settings-store';
+import { useLocaleStore } from '../../stores/locale-store';
+import {
+  shareAttachment, downloadAttachment, shareAttachmentViaSheet, cacheBlobFile, fetchBlobBytes,
+  shareBytes, writeTempFile, shareLocalFile,
+} from '../../lib/email-export';
+import {
+  getAttachmentDisplayName, visibleAttachments, previewKindFor, formatSize,
+} from '../../lib/attachment-display';
+import { emailExportFilename } from '../../lib/download-filename';
+import { ActionSheet, type ActionSheetItem } from './ActionSheet';
+import { AttachmentPreviewModal, type PreviewItem } from './AttachmentPreviewModal';
+import { unwrapEmbeddedMessage, type ExtractedAttachment } from './use-body-override';
+
+interface Props {
+  email: Email;
+  jmapAccountId?: string;
+  calendarBannerShown: boolean;
+  tnefUnpacked?: boolean;
+  /** Parts extracted client-side (TNEF / embedded message). */
+  extracted?: ExtractedAttachment[];
+}
+
+type Item =
+  | { key: string; kind: 'blob'; att: Attachment; name: string; type: string; size?: number }
+  | { key: string; kind: 'bytes'; part: ExtractedAttachment; name: string; type: string; size?: number };
+
+const MAX_BUNDLE_BYTES = 100 * 1024 * 1024;
+
+/**
+ * Attachment chips: tap follows the "attachment click action" setting
+ * (in-app preview when the type supports it, else the platform viewer /
+ * save), long-press opens Preview / Open / Save / Share, and "Download all"
+ * bundles every part into a zip named by the export template.
+ */
+export function AttachmentChips({ email, jmapAccountId, calendarBannerShown, tnefUnpacked, extracted }: Props) {
+  const c = useColors();
+  const styles = React.useMemo(() => makeStyles(c), [c]);
+  const t = useLocaleStore((s) => s.t);
+  const hideInlineImageAttachments = useSettingsStore((s) => s.hideInlineImageAttachments);
+  const mailAttachmentAction = useSettingsStore((s) => s.mailAttachmentAction);
+  const exportOpts = useSettingsStore((s) => ({
+    spaceReplacement: s.exportSpaceReplacement,
+    lowercase: s.exportLowercase,
+    stripDiacritics: s.exportStripDiacritics,
+  }));
+
+  const [expanded, setExpanded] = React.useState(false);
+  const [busyKey, setBusyKey] = React.useState<string | null>(null);
+  const [sheetItem, setSheetItem] = React.useState<Item | null>(null);
+  const [preview, setPreview] = React.useState<PreviewItem | null>(null);
+  const [previewLoading, setPreviewLoading] = React.useState(false);
+  const previewSource = React.useRef<Item | null>(null);
+
+  const items = React.useMemo<Item[]>(() => {
+    const blobs = visibleAttachments(email, { hideInlineImageAttachments, calendarBannerShown, tnefUnpacked })
+      .map<Item>((att, i) => ({
+        key: att.blobId || `att-${i}`,
+        kind: 'blob',
+        att,
+        name: getAttachmentDisplayName(att.name, att.type),
+        type: att.type || 'application/octet-stream',
+        size: att.size,
+      }));
+    const extra = (extracted ?? []).map<Item>((part, i) => ({
+      key: `x-${i}-${part.name}`,
+      kind: 'bytes',
+      part,
+      name: getAttachmentDisplayName(part.name, part.type),
+      type: part.type,
+      size: part.size,
+    }));
+    return [...blobs, ...extra];
+  }, [email, hideInlineImageAttachments, calendarBannerShown, tnefUnpacked, extracted]);
+
+  if (items.length === 0) return null;
+
+  const run = async (key: string, fn: () => Promise<void>, failTitle: string) => {
+    if (busyKey) return;
+    setBusyKey(key);
+    try {
+      await fn();
+    } catch (e) {
+      Alert.alert(failTitle, e instanceof Error ? e.message : String(e));
+    } finally {
+      setBusyKey(null);
+    }
+  };
+
+  const open = (item: Item) => run(item.key, async () => {
+    if (item.kind === 'blob') await shareAttachment(item.att.blobId, item.att.name, item.att.type, email, jmapAccountId);
+    else await shareBytes(item.part.bytes, item.name, item.type);
+  }, t('email_viewer.attachment_failed', 'Could not open attachment'));
+
+  const save = (item: Item) => run(item.key, async () => {
+    if (item.kind === 'blob') await downloadAttachment(item.att.blobId, item.att.name, item.att.type, email, jmapAccountId);
+    else await shareBytes(item.part.bytes, item.name, item.type, { forceSheet: true });
+  }, t('email_viewer.attachment_failed', 'Could not save attachment'));
+
+  const share = (item: Item) => run(item.key, async () => {
+    if (item.kind === 'blob') await shareAttachmentViaSheet(item.att.blobId, item.att.name, item.att.type, email, jmapAccountId);
+    else await shareBytes(item.part.bytes, item.name, item.type, { forceSheet: true });
+  }, t('email_viewer.attachment_failed', 'Could not share attachment'));
+
+  const showPreview = (item: Item) => {
+    const kind = previewKindFor({ name: item.name, type: item.type });
+    if (kind === 'none') { void open(item); return; }
+    previewSource.current = item;
+    setPreviewLoading(true);
+    setPreview(null);
+    void (async () => {
+      try {
+        if (kind === 'text' || kind === 'eml') {
+          const bytes = item.kind === 'blob'
+            ? await fetchBlobBytes(item.att.blobId, item.att.name, item.att.type, jmapAccountId)
+            : item.part.bytes;
+          if (kind === 'eml') {
+            const res = await unwrapEmbeddedMessage(bytes);
+            const { default: PostalMime } = await import('postal-mime');
+            const parsed = await PostalMime.parse(bytes, { attachmentEncoding: 'arraybuffer' });
+            const from = parsed.from && 'address' in parsed.from
+              ? `${parsed.from.name ? `${parsed.from.name} ` : ''}<${parsed.from.address}>`
+              : parsed.from?.name;
+            setPreview({
+              kind, name: item.name, mimeType: item.type,
+              eml: { subject: parsed.subject, from, date: parsed.date, html: res.html, text: res.text },
+            });
+          } else {
+            setPreview({ kind, name: item.name, mimeType: item.type, text: new TextDecoder('utf-8').decode(bytes) });
+          }
+          return;
+        }
+        const file = item.kind === 'blob'
+          ? await cacheBlobFile(item.att.blobId, item.name, item.type, jmapAccountId)
+          : writeTempFile(item.part.bytes, item.name, item.type);
+        setPreview({ kind, name: item.name, mimeType: item.type, fileUri: file.uri });
+      } catch (e) {
+        setPreview(null);
+        Alert.alert(t('email_viewer.attachment_failed', 'Could not open attachment'), e instanceof Error ? e.message : String(e));
+      } finally {
+        setPreviewLoading(false);
+      }
+    })();
+  };
+
+  const onTap = (item: Item) => {
+    if (mailAttachmentAction === 'download') void save(item);
+    else showPreview(item);
+  };
+
+  const downloadAll = () => run('__all__', async () => {
+    const total = items.reduce((n, i) => n + (i.size ?? 0), 0);
+    if (total > MAX_BUNDLE_BYTES) throw new Error(t('email_viewer.bundle_too_large', 'The attachments are too large to bundle.'));
+    const { default: JSZip } = await import('jszip');
+    const zip = new JSZip();
+    const used = new Set<string>();
+    for (const item of items) {
+      let name = item.name;
+      if (used.has(name)) {
+        const dot = name.lastIndexOf('.');
+        name = dot > 0 ? `${name.slice(0, dot)} (${used.size})${name.slice(dot)}` : `${name} (${used.size})`;
+      }
+      used.add(name);
+      const bytes = item.kind === 'blob'
+        ? await fetchBlobBytes(item.att.blobId, item.att.name, item.att.type, jmapAccountId)
+        : item.part.bytes;
+      zip.file(name, bytes);
+    }
+    const out = await zip.generateAsync({ type: 'uint8array' });
+    const stem = emailExportFilename(email, { ...exportOpts, template: '{date} {subject}' }).replace(/\.eml$/i, '');
+    await shareBytes(out, `${stem}.zip`, 'application/zip', { forceSheet: true });
+  }, t('email_viewer.attachment_failed', 'Could not bundle attachments'));
+
+  const visible = expanded ? items : items.slice(0, 3);
+  const sheetActions: ActionSheetItem[] = sheetItem ? [
+    ...(previewKindFor({ name: sheetItem.name, type: sheetItem.type }) !== 'none' ? [{
+      key: 'preview',
+      label: t('email_viewer.attachment_actions.preview', 'Preview'),
+      icon: <Eye size={18} color={c.textSecondary} />,
+      onPress: () => { const it = sheetItem; setSheetItem(null); showPreview(it); },
+    }] : []),
+    {
+      key: 'open',
+      label: t('email_viewer.attachment_actions.open', 'Open'),
+      icon: <ExternalLink size={18} color={c.textSecondary} />,
+      onPress: () => { const it = sheetItem; setSheetItem(null); void open(it); },
+    },
+    {
+      key: 'save',
+      label: t('email_viewer.attachment_actions.save', 'Save'),
+      icon: <Save size={18} color={c.textSecondary} />,
+      onPress: () => { const it = sheetItem; setSheetItem(null); void save(it); },
+    },
+    {
+      key: 'share',
+      label: t('email_viewer.attachment_actions.share', 'Share'),
+      icon: <Share2 size={18} color={c.textSecondary} />,
+      onPress: () => { const it = sheetItem; setSheetItem(null); void share(it); },
+    },
+  ] : [];
+
+  return (
+    <View style={styles.block}>
+      <View style={styles.row}>
+        {visible.map((item) => {
+          const busy = busyKey === item.key;
+          return (
+            <Pressable
+              key={item.key}
+              style={({ pressed }) => [styles.chip, pressed && styles.chipPressed]}
+              onPress={() => onTap(item)}
+              onLongPress={() => setSheetItem(item)}
+              disabled={!!busyKey}
+              accessibilityLabel={item.name}
+            >
+              {busy ? <ActivityIndicator size="small" color={c.textMuted} /> : <Paperclip size={14} color={c.textMuted} />}
+              <Text style={styles.name} numberOfLines={1}>{item.name}</Text>
+              <Text style={styles.size}>{formatSize(item.size)}</Text>
+              <Download size={14} color={c.textMuted} />
+            </Pressable>
+          );
+        })}
+      </View>
+      <View style={styles.footer}>
+        {items.length > 3 && (
+          <Pressable onPress={() => setExpanded((v) => !v)} style={styles.link} hitSlop={6}>
+            <Text style={styles.linkText}>
+              {expanded
+                ? t('email_viewer.show_less', 'Show less')
+                : t('email_viewer.show_all_count', 'Show all ({count})', { count: items.length })}
+            </Text>
+          </Pressable>
+        )}
+        {items.length > 1 && (
+          <Pressable onPress={downloadAll} style={styles.link} hitSlop={6} disabled={!!busyKey}>
+            {busyKey === '__all__' ? <ActivityIndicator size="small" color={c.primary} /> : <FolderArchive size={14} color={c.primary} />}
+            <Text style={styles.linkText}>{t('email_viewer.download_all', 'Download all')}</Text>
+          </Pressable>
+        )}
+      </View>
+
+      <ActionSheet
+        visible={!!sheetItem}
+        title={sheetItem?.name ?? ''}
+        subtitle={sheetItem ? `${sheetItem.type}${sheetItem.size ? ` · ${formatSize(sheetItem.size)}` : ''}` : undefined}
+        items={sheetActions}
+        onClose={() => setSheetItem(null)}
+      />
+
+      <AttachmentPreviewModal
+        item={preview}
+        loading={previewLoading}
+        onClose={() => { setPreview(null); setPreviewLoading(false); }}
+        onOpenExternal={() => {
+          const it = previewSource.current;
+          if (!it) return;
+          if (preview?.fileUri && it.kind === 'blob') {
+            void run(it.key, () => shareAttachment(it.att.blobId, it.att.name, it.att.type, email, jmapAccountId), t('email_viewer.attachment_failed', 'Could not open attachment'));
+          } else {
+            void open(it);
+          }
+        }}
+        onShare={() => {
+          const it = previewSource.current;
+          if (!it) return;
+          if (preview?.fileUri) {
+            const { File } = require('expo-file-system') as typeof import('expo-file-system');
+            void shareLocalFile(new File(preview.fileUri), it.type, it.name, { forceSheet: true }).catch(() => undefined);
+          } else {
+            void share(it);
+          }
+        }}
+      />
+    </View>
+  );
+}
+
+function makeStyles(c: ThemePalette) {
+  return StyleSheet.create({
+    block: {
+      backgroundColor: c.background,
+      paddingHorizontal: spacing.lg,
+      paddingVertical: spacing.sm,
+      gap: spacing.xs,
+    },
+    row: { flexDirection: 'row', flexWrap: 'wrap', gap: spacing.xs },
+    chip: {
+      flexDirection: 'row',
+      alignItems: 'center',
+      gap: spacing.xs,
+      paddingHorizontal: spacing.sm,
+      paddingVertical: 6,
+      backgroundColor: c.surface,
+      borderWidth: 1,
+      borderColor: c.border,
+      borderRadius: radius.sm,
+    },
+    chipPressed: { backgroundColor: c.surfaceHover, opacity: 0.85 },
+    name: { ...typography.caption, color: c.text, maxWidth: 180 },
+    size: { ...typography.small, color: c.textMuted },
+    footer: { flexDirection: 'row', gap: spacing.lg, alignItems: 'center' },
+    link: { flexDirection: 'row', alignItems: 'center', gap: 4, paddingVertical: 4 },
+    linkText: { ...typography.caption, color: c.primary, fontWeight: '600' },
+  });
+}
diff --git a/src/components/email/AttachmentPreviewModal.tsx b/src/components/email/AttachmentPreviewModal.tsx
new file mode 100644
index 00000000..72864249
--- /dev/null
+++ b/src/components/email/AttachmentPreviewModal.tsx
@@ -0,0 +1,193 @@
+import React from 'react';
+import {
+  View, Text, StyleSheet, Modal, Pressable, ScrollView, Image, ActivityIndicator, Platform, useWindowDimensions,
+} from 'react-native';
+import { SafeAreaView } from 'react-native-safe-area-context';
+import { WebView } from 'react-native-webview';
+import { X, ExternalLink, Share2 } from 'lucide-react-native';
+import type { Email } from '../../api/types';
+import { spacing, radius, typography, componentSizes, type ThemePalette } from '../../theme/tokens';
+import { useColors } from '../../theme/colors';
+import { useLocaleStore } from '../../stores/locale-store';
+import EmailBodyView from '../EmailBodyView';
+import type { PreviewKind } from '../../lib/attachment-display';
+
+export interface PreviewItem {
+  kind: PreviewKind;
+  name: string;
+  mimeType: string;
+  /** Local file:// URI for images and PDFs. */
+  fileUri?: string;
+  /** Decoded text for text-like parts. */
+  text?: string;
+  /** Parsed embedded message for .eml previews. */
+  eml?: { subject?: string; from?: string; date?: string; html: string | null; text: string | null };
+}
+
+interface Props {
+  item: PreviewItem | null;
+  loading: boolean;
+  onClose: () => void;
+  /** Hand the file to an external app (PDF on Android, unsupported types). */
+  onOpenExternal: () => void;
+  onShare: () => void;
+}
+
+/**
+ * In-app preview for images, PDFs (iOS renders them in the WebView; Android
+ * has no built-in PDF renderer, so it offers the external viewer), text and
+ * embedded messages. Anything else goes to the external viewer / share sheet.
+ */
+export function AttachmentPreviewModal({ item, loading, onClose, onOpenExternal, onShare }: Props) {
+  const c = useColors();
+  const styles = React.useMemo(() => makeStyles(c), [c]);
+  const t = useLocaleStore((s) => s.t);
+  const { width } = useWindowDimensions();
+
+  const emlEmail = React.useMemo<Email | null>(() => {
+    if (!item?.eml) return null;
+    return {
+      id: `eml-preview-${item.name}`,
+      threadId: '',
+      mailboxIds: {},
+      keywords: {},
+      size: 0,
+      receivedAt: item.eml.date ?? new Date().toISOString(),
+      hasAttachment: false,
+      subject: item.eml.subject,
+    };
+  }, [item]);
+
+  const renderBody = () => {
+    if (loading || !item) {
+      return (
+        <View style={styles.centered}>
+          <ActivityIndicator color={c.primary} />
+        </View>
+      );
+    }
+    switch (item.kind) {
+      case 'image':
+        return (
+          <ScrollView
+            style={styles.flex}
+            contentContainerStyle={styles.imageScroll}
+            maximumZoomScale={4}
+            minimumZoomScale={1}
+            bouncesZoom
+          >
+            <Image source={{ uri: item.fileUri }} style={{ width: width - spacing.lg * 2, height: width * 1.2 }} resizeMode="contain" />
+          </ScrollView>
+        );
+      case 'pdf':
+        if (Platform.OS === 'ios' && item.fileUri) {
+          return (
+            <WebView
+              source={{ uri: item.fileUri }}
+              originWhitelist={['file://*']}
+              allowFileAccess
+              allowingReadAccessToURL={item.fileUri}
+              style={styles.flex}
+              javaScriptEnabled={false}
+              setSupportMultipleWindows={false}
+              onShouldStartLoadWithRequest={(req) => req.url === item.fileUri}
+            />
+          );
+        }
+        return (
+          <View style={styles.centered}>
+            <Text style={styles.hint}>{t('email_viewer.preview.pdf_external', 'PDFs open in your PDF viewer on this device.')}</Text>
+            <Pressable style={styles.button} onPress={onOpenExternal}>
+              <ExternalLink size={16} color={c.primaryForeground} />
+              <Text style={styles.buttonText}>{t('email_viewer.preview.open_external', 'Open in app')}</Text>
+            </Pressable>
+          </View>
+        );
+      case 'text':
+        return (
+          <ScrollView style={styles.flex} contentContainerStyle={styles.textScroll}>
+            <Text selectable style={styles.text}>{item.text ?? ''}</Text>
+          </ScrollView>
+        );
+      case 'eml':
+        return (
+          <ScrollView style={styles.flex}>
+            <View style={styles.emlHeader}>
+              <Text style={styles.emlSubject}>{item.eml?.subject || t('email_viewer.no_subject', '(No Subject)')}</Text>
+              {item.eml?.from ? <Text style={styles.emlMeta}>{item.eml.from}</Text> : null}
+              {item.eml?.date ? <Text style={styles.emlMeta}>{item.eml.date}</Text> : null}
+            </View>
+            {emlEmail && (
+              <EmailBodyView
+                email={emlEmail}
+                bodyOverride={{ html: item.eml?.html, text: item.eml?.text }}
+              />
+            )}
+          </ScrollView>
+        );
+      default:
+        return (
+          <View style={styles.centered}>
+            <Text style={styles.hint}>{t('email_viewer.preview.unsupported', 'No preview for this file type.')}</Text>
+            <Pressable style={styles.button} onPress={onOpenExternal}>
+              <ExternalLink size={16} color={c.primaryForeground} />
+              <Text style={styles.buttonText}>{t('email_viewer.preview.open_external', 'Open in app')}</Text>
+            </Pressable>
+          </View>
+        );
+    }
+  };
+
+  return (
+    <Modal visible={!!item || loading} animationType="slide" onRequestClose={onClose}>
+      <SafeAreaView style={styles.container} edges={['top', 'bottom']}>
+        <View style={styles.header}>
+          <Pressable onPress={onClose} style={styles.headerBtn} hitSlop={8}>
+            <X size={22} color={c.text} />
+          </Pressable>
+          <Text style={styles.title} numberOfLines={1}>{item?.name ?? ''}</Text>
+          <Pressable onPress={onShare} style={styles.headerBtn} hitSlop={8} disabled={!item}>
+            <Share2 size={20} color={item ? c.text : c.textMuted} />
+          </Pressable>
+        </View>
+        {renderBody()}
+      </SafeAreaView>
+    </Modal>
+  );
+}
+
+function makeStyles(c: ThemePalette) {
+  return StyleSheet.create({
+    container: { flex: 1, backgroundColor: c.background },
+    flex: { flex: 1 },
+    header: {
+      flexDirection: 'row',
+      alignItems: 'center',
+      height: componentSizes.headerHeight,
+      paddingHorizontal: spacing.lg,
+      borderBottomWidth: 1,
+      borderBottomColor: c.border,
+      gap: spacing.sm,
+    },
+    headerBtn: { width: 40, height: 40, alignItems: 'center', justifyContent: 'center', borderRadius: radius.md },
+    title: { ...typography.h3, color: c.text, flex: 1 },
+    centered: { flex: 1, alignItems: 'center', justifyContent: 'center', padding: spacing.lg, gap: spacing.md },
+    hint: { ...typography.body, color: c.textMuted, textAlign: 'center' },
+    button: {
+      flexDirection: 'row',
+      alignItems: 'center',
+      gap: spacing.xs,
+      backgroundColor: c.primary,
+      paddingHorizontal: spacing.lg,
+      paddingVertical: spacing.sm,
+      borderRadius: radius.md,
+    },
+    buttonText: { ...typography.bodySemibold, color: c.primaryForeground },
+    imageScroll: { alignItems: 'center', justifyContent: 'center', padding: spacing.lg, flexGrow: 1 },
+    textScroll: { padding: spacing.lg },
+    text: { fontFamily: 'monospace', fontSize: 12, lineHeight: 18, color: c.text },
+    emlHeader: { padding: spacing.lg, borderBottomWidth: 1, borderBottomColor: c.border, gap: 2 },
+    emlSubject: { ...typography.bodySemibold, color: c.text },
+    emlMeta: { ...typography.caption, color: c.textSecondary },
+  });
+}
diff --git a/src/components/email/MessageContent.tsx b/src/components/email/MessageContent.tsx
new file mode 100644
index 00000000..19f38a93
--- /dev/null
+++ b/src/components/email/MessageContent.tsx
@@ -0,0 +1,130 @@
+import React from 'react';
+import { View, StyleSheet, ActivityIndicator } from 'react-native';
+import type { Email, EmailAddress, Identity } from '../../api/types';
+import { spacing, type ThemePalette } from '../../theme/tokens';
+import { useColors } from '../../theme/colors';
+import { useSettingsStore } from '../../stores/settings-store';
+import EmailBodyView from '../EmailBodyView';
+import { CalendarInvitationBanner } from './CalendarInvitationBanner';
+import { MessageHeader } from './MessageHeader';
+import { AttachmentChips } from './AttachmentChips';
+import { UnsubscribeBanner } from './UnsubscribeBanner';
+import { ReadReceiptBanner } from './ReadReceiptBanner';
+import { useBodyOverride } from './use-body-override';
+import { deriveHeaderInfo } from '../../lib/email-headers';
+import { calendarBannerShownFor } from '../../lib/attachment-display';
+
+export interface MessageContentProps {
+  email: Email;
+  jmapAccountId?: string;
+  identities: Identity[];
+  currentMailboxRole?: string | null;
+  themeOverride?: 'light' | 'dark' | null;
+  onSwipe?: (direction: 'prev' | 'next') => void;
+  onZoomChange?: (zoom: { pinching: boolean; zoomed: boolean }) => void;
+  onToggleStar?: (email: Email) => void;
+  onAddressPress: (address: EmailAddress) => void;
+  /** Reflect a local keyword change (e.g. `$mdnsent`) in the caller's cache. */
+  onEmailPatched: (email: Email) => void;
+  /** Compact header (thread cards). */
+  compact?: boolean;
+}
+
+/**
+ * Everything below the subject for one message: header block with details,
+ * receipt / unsubscribe banners, attachment chips, calendar invitation and
+ * the body. Used both by the single-message pane and by expanded thread
+ * cards.
+ */
+export function MessageContent({
+  email, jmapAccountId, identities, currentMailboxRole, themeOverride, onSwipe, onZoomChange,
+  onToggleStar, onAddressPress, onEmailPatched, compact,
+}: MessageContentProps) {
+  const c = useColors();
+  const styles = React.useMemo(() => makeStyles(c), [c]);
+  const attachmentPosition = useSettingsStore((s) => s.attachmentPosition);
+  const calendarParsing = useSettingsStore((s) => s.calendarInvitationParsingEnabled);
+  const headerInfo = React.useMemo(() => deriveHeaderInfo(email), [email]);
+  const unwrap = useBodyOverride(email, jmapAccountId);
+  const calendarBannerShown = calendarBannerShownFor(email, calendarParsing);
+  const from = email.from?.[0];
+
+  const chips = (
+    <AttachmentChips
+      email={email}
+      jmapAccountId={jmapAccountId}
+      calendarBannerShown={calendarBannerShown}
+      tnefUnpacked={unwrap.tnefUnpacked}
+      extracted={unwrap.extracted}
+    />
+  );
+
+  return (
+    <View>
+      <View style={styles.headerBlock}>
+        <MessageHeader
+          email={email}
+          identities={identities}
+          headerInfo={headerInfo}
+          onToggleStar={onToggleStar}
+          onAddressPress={onAddressPress}
+          compact={compact}
+        />
+        {attachmentPosition === 'beside-sender' && chips}
+      </View>
+      {attachmentPosition === 'below-header' && <View style={styles.chipsBlock}>{chips}</View>}
+
+      {headerInfo.readReceiptRequestedBy && (
+        <ReadReceiptBanner
+          email={email}
+          requestedBy={headerInfo.readReceiptRequestedBy}
+          jmapAccountId={jmapAccountId}
+          currentMailboxRole={currentMailboxRole}
+          onHandled={onEmailPatched}
+        />
+      )}
+      {headerInfo.list.listUnsubscribe?.preferred && (
+        <UnsubscribeBanner
+          email={email}
+          list={headerInfo.list}
+          messageKey={headerInfo.messageId ?? email.id}
+          jmapAccountId={jmapAccountId}
+        />
+      )}
+
+      <CalendarInvitationBanner email={email} jmapAccountId={jmapAccountId} />
+
+      <View style={styles.body}>
+        {unwrap.loading ? (
+          <View style={styles.loading}><ActivityIndicator color={c.primary} /></View>
+        ) : (
+          <EmailBodyView
+            email={email}
+            senderEmail={from?.email}
+            jmapAccountId={jmapAccountId}
+            onSwipe={onSwipe}
+            onZoomChange={onZoomChange}
+            themeOverride={themeOverride}
+            bodyOverride={unwrap.override}
+          />
+        )}
+      </View>
+    </View>
+  );
+}
+
+function makeStyles(c: ThemePalette) {
+  return StyleSheet.create({
+    headerBlock: {
+      backgroundColor: c.background,
+      borderBottomWidth: 1,
+      borderBottomColor: c.border,
+    },
+    chipsBlock: {
+      borderBottomWidth: 1,
+      borderBottomColor: c.border,
+    },
+    body: { backgroundColor: c.background },
+    loading: { padding: spacing.xl, alignItems: 'center' },
+  });
+}
diff --git a/src/components/email/MessageHeader.tsx b/src/components/email/MessageHeader.tsx
new file mode 100644
index 00000000..c46db46f
--- /dev/null
+++ b/src/components/email/MessageHeader.tsx
@@ -0,0 +1,356 @@
+import React from 'react';
+import { View, Text, StyleSheet, Pressable } from 'react-native';
+import {
+  Star, ChevronDown, ChevronUp, Reply, Forward, ShieldCheck, ShieldAlert, ShieldQuestion, Lock,
+} from 'lucide-react-native';
+import type { Email, EmailAddress, Identity } from '../../api/types';
+import { spacing, radius, typography, componentSizes, type ThemePalette } from '../../theme/tokens';
+import { useColors } from '../../theme/colors';
+import SenderAvatar from '../SenderAvatar';
+import { useSettingsStore } from '../../stores/settings-store';
+import { useLocaleStore } from '../../stores/locale-store';
+import { useKeywordsStore, keywordToken } from '../../stores/keywords-store';
+import { emailDisplayDate, formatHeaderDate, formatHeaderTime, formatFullDateTime } from '../../lib/email-date';
+import {
+  deriveHeaderInfo, deliveryDeltaMs, formatDelta, isAuthenticationSpoofed, findReceivingIdentity,
+  type AuthenticationResults, type EmailHeaderInfo,
+} from '../../lib/email-headers';
+import { formatSize } from '../../lib/attachment-display';
+import { isSmimeEmail } from '../../lib/smime';
+
+interface Props {
+  email: Email;
+  identities: Identity[];
+  headerInfo?: EmailHeaderInfo;
+  onToggleStar?: (email: Email) => void;
+  onAddressPress: (address: EmailAddress) => void;
+  /** Compact variant for collapsed thread cards. */
+  compact?: boolean;
+}
+
+function addressLabel(a: EmailAddress): string {
+  return a.name || a.email;
+}
+
+function AddressList({
+  label, addresses, onPress, styles,
+}: { label: string; addresses: EmailAddress[] | undefined; onPress: (a: EmailAddress) => void; styles: ReturnType<typeof makeStyles> }) {
+  if (!addresses || addresses.length === 0) return null;
+  return (
+    <Text style={styles.recipients} numberOfLines={2}>
+      <Text style={styles.recipientsLabel}>{label} </Text>
+      {addresses.map((a, i) => (
+        <Text key={`${a.email}-${i}`} onPress={() => onPress(a)} style={styles.recipientLink}>
+          {addressLabel(a)}{i < addresses.length - 1 ? ', ' : ''}
+        </Text>
+      ))}
+    </Text>
+  );
+}
+
+function authTone(result?: string): 'ok' | 'warn' | 'bad' | 'none' {
+  switch (result) {
+    case 'pass': return 'ok';
+    case 'fail':
+    case 'permerror': return 'bad';
+    case 'softfail':
+    case 'neutral':
+    case 'temperror': return 'warn';
+    default: return 'none';
+  }
+}
+
+function AuthChip({ label, result, styles, c }: { label: string; result?: string; styles: ReturnType<typeof makeStyles>; c: ThemePalette }) {
+  const tone = authTone(result);
+  const color = tone === 'ok' ? c.success : tone === 'bad' ? c.error : tone === 'warn' ? c.warning : c.textMuted;
+  const Icon = tone === 'ok' ? ShieldCheck : tone === 'bad' ? ShieldAlert : ShieldQuestion;
+  return (
+    <View style={[styles.chip, { borderColor: color }]}>
+      <Icon size={12} color={color} />
+      <Text style={[styles.chipText, { color }]}>{label} {result ?? '-'}</Text>
+    </View>
+  );
+}
+
+function DetailRow({ label, value, styles, mono }: { label: string; value?: string | null; styles: ReturnType<typeof makeStyles>; mono?: boolean }) {
+  if (!value) return null;
+  return (
+    <View style={styles.detailRow}>
+      <Text style={styles.detailLabel}>{label}</Text>
+      <Text style={[styles.detailValue, mono && styles.detailMono]} selectable>{value}</Text>
+    </View>
+  );
+}
+
+/**
+ * Sender / recipient / date block of a message, with the collapsible
+ * "Show details" panel (recipients & routing, authentication, identifiers,
+ * mailing list, properties) the webmail viewer shows.
+ */
+export function MessageHeader({ email, identities, headerInfo, onToggleStar, onAddressPress, compact }: Props) {
+  const c = useColors();
+  const styles = React.useMemo(() => makeStyles(c), [c]);
+  const t = useLocaleStore((s) => s.t);
+  const locale = useLocaleStore((s) => s.locale);
+  const timeFormat = useSettingsStore((s) => s.timeFormat);
+  const keywordDefs = useKeywordsStore((s) => s.keywords);
+  const [showDetails, setShowDetails] = React.useState(false);
+  React.useEffect(() => { setShowDetails(false); }, [email.id]);
+
+  const info = React.useMemo(() => headerInfo ?? deriveHeaderInfo(email), [headerInfo, email]);
+  const from = email.from?.[0];
+  const starred = !!email.keywords?.$flagged;
+  const displayDate = emailDisplayDate(email);
+  const spoofed = isAuthenticationSpoofed(info.auth);
+
+  // "via <identity>": the message was sent by one of the user's identities or
+  // received at one of them (incl. +tag); hidden when the From can't be
+  // trusted so a forged From doesn't get a legitimacy badge.
+  const viaIdentity = React.useMemo(() => {
+    if (spoofed || identities.length === 0) return null;
+    const fromEmail = from?.email?.toLowerCase();
+    const sentAs = fromEmail ? identities.find((i) => i.email?.toLowerCase() === fromEmail) : undefined;
+    if (sentAs) return { identity: sentAs, direction: 'from' as const };
+    const received = findReceivingIdentity(identities, email);
+    if (received && identities.length > 1 && received.id !== identities[0].id) {
+      return { identity: received, direction: 'to' as const };
+    }
+    return null;
+  }, [spoofed, identities, from?.email, email]);
+
+  const tags = React.useMemo(
+    () => keywordDefs.filter((kw) => !!email.keywords?.[keywordToken(kw.id)]),
+    [keywordDefs, email.keywords],
+  );
+  const important = !!email.keywords?.$important;
+  const answered = !!email.keywords?.$answered;
+  const forwarded = !!email.keywords?.$forwarded;
+  const smime = React.useMemo(() => isSmimeEmail(email), [email]);
+  const delta = deliveryDeltaMs(email);
+
+  const auth: AuthenticationResults | undefined = info.auth;
+  const hasAuth = !!(auth && (auth.spf || auth.dkim || auth.dmarc || auth.iprev));
+  const attachmentsSummary = email.attachments?.length
+    ? `${email.attachments.length} · ${formatSize(email.attachments.reduce((n, a) => n + (a.size ?? 0), 0))}`
+    : null;
+
+  return (
+    <View style={styles.block}>
+      <View style={styles.row}>
+        <Pressable onPress={from ? () => onAddressPress(from) : undefined} hitSlop={4}>
+          <SenderAvatar name={from?.name} email={from?.email} size={compact ? componentSizes.avatarSm : componentSizes.avatarMd} />
+        </Pressable>
+        <View style={styles.info}>
+          <Pressable onPress={from ? () => onAddressPress(from) : undefined}>
+            <Text style={styles.name} numberOfLines={1}>
+              {from?.name || from?.email || t('email_viewer.unknown_sender', 'Unknown')}
+            </Text>
+            {from?.name && from?.email ? (
+              <Text style={styles.email} numberOfLines={1}>{from.email}</Text>
+            ) : null}
+          </Pressable>
+          {!compact && (
+            <>
+              <AddressList label={t('email_viewer.to', 'To').toLowerCase()} addresses={email.to} onPress={onAddressPress} styles={styles} />
+              <AddressList label={t('email_viewer.cc', 'CC').toLowerCase()} addresses={email.cc} onPress={onAddressPress} styles={styles} />
+              <AddressList label={t('email_viewer.bcc', 'BCC').toLowerCase()} addresses={email.bcc} onPress={onAddressPress} styles={styles} />
+              <AddressList label={t('email_viewer.reply_to_label', 'Reply-To:').replace(/:$/, '').toLowerCase()} addresses={email.replyTo} onPress={onAddressPress} styles={styles} />
+            </>
+          )}
+        </View>
+        <View style={styles.meta}>
+          <Text style={styles.date}>{formatHeaderDate(displayDate, locale)}</Text>
+          <Text style={styles.time}>
+            {formatHeaderTime(displayDate, timeFormat, locale)}
+            {!compact && email.size > 0 ? ` · ${formatSize(email.size)}` : ''}
+          </Text>
+          {onToggleStar && (
+            <Pressable onPress={() => onToggleStar(email)} hitSlop={8} style={styles.star}>
+              <Star size={16} color={starred ? c.starred : c.textMuted} fill={starred ? c.starred : 'transparent'} />
+            </Pressable>
+          )}
+        </View>
+      </View>
+
+      {(tags.length > 0 || important || answered || forwarded || viaIdentity || smime) && (
+        <View style={styles.badges}>
+          {important && (
+            <View style={[styles.badge, { backgroundColor: c.warningBg }]}>
+              <Text style={[styles.badgeText, { color: c.warning }]}>{t('email_viewer.important', 'Important')}</Text>
+            </View>
+          )}
+          {tags.map((kw) => {
+            const palette = c.tags[kw.color];
+            return (
+              <View key={kw.id} style={[styles.badge, { backgroundColor: palette.bg }]}>
+                <View style={[styles.badgeDot, { backgroundColor: palette.dot }]} />
+                <Text style={[styles.badgeText, { color: palette.text }]}>{kw.label}</Text>
+              </View>
+            );
+          })}
+          {answered && (
+            <View style={styles.badge}>
+              <Reply size={11} color={c.textMuted} />
+              <Text style={styles.badgeText}>{t('email_viewer.replied', 'Replied')}</Text>
+            </View>
+          )}
+          {forwarded && (
+            <View style={styles.badge}>
+              <Forward size={11} color={c.textMuted} />
+              <Text style={styles.badgeText}>{t('email_viewer.forwarded', 'Forwarded')}</Text>
+            </View>
+          )}
+          {viaIdentity && (
+            <View style={[styles.badge, { backgroundColor: c.primaryBg }]}>
+              <Text style={[styles.badgeText, { color: c.primary }]}>
+                {viaIdentity.direction === 'from'
+                  ? t('identities.badge.identity_short', 'via {name}', { name: viaIdentity.identity.email })
+                  : t('email_viewer.received_via', 'to {name}', { name: viaIdentity.identity.email })}
+              </Text>
+            </View>
+          )}
+          {smime && (
+            <View style={styles.badge}>
+              <Lock size={11} color={c.textMuted} />
+              <Text style={styles.badgeText}>{t('email_viewer.smime_unsupported', 'Signed/encrypted with S/MIME - not supported on mobile')}</Text>
+            </View>
+          )}
+        </View>
+      )}
+
+      {!compact && (
+        <Pressable onPress={() => setShowDetails((v) => !v)} style={styles.detailsToggle} hitSlop={6}>
+          {showDetails ? <ChevronUp size={14} color={c.primary} /> : <ChevronDown size={14} color={c.primary} />}
+          <Text style={styles.detailsToggleText}>
+            {showDetails ? t('email_viewer.hide_details', 'Hide details') : t('email_viewer.show_details', 'Show details')}
+          </Text>
+        </Pressable>
+      )}
+
+      {showDetails && (
+        <View style={styles.details}>
+          <Text style={styles.detailsSection}>{t('email_viewer.details.recipients_routing', 'Recipients & routing')}</Text>
+          <DetailRow label={t('email_viewer.from', 'From')} value={from ? `${from.name ? `${from.name} ` : ''}<${from.email}>` : undefined} styles={styles} />
+          <DetailRow label={t('email_viewer.to', 'To')} value={email.to?.map((a) => a.name ? `${a.name} <${a.email}>` : a.email).join(', ')} styles={styles} />
+          <DetailRow label={t('email_viewer.cc', 'CC')} value={email.cc?.map((a) => a.name ? `${a.name} <${a.email}>` : a.email).join(', ')} styles={styles} />
+          <DetailRow label={t('email_viewer.bcc', 'BCC')} value={email.bcc?.map((a) => a.name ? `${a.name} <${a.email}>` : a.email).join(', ')} styles={styles} />
+          <DetailRow label={t('email_viewer.details.sent', 'Sent')} value={formatFullDateTime(email.sentAt, timeFormat, locale)} styles={styles} />
+          <DetailRow
+            label={t('email_viewer.details.received', 'Received')}
+            value={`${formatFullDateTime(email.receivedAt, timeFormat, locale)}${delta !== null && delta > 60000 ? ` · ${formatDelta(delta)} ${t('email_viewer.details.delivery_time', 'Delivery time').toLowerCase()}` : ''}`}
+            styles={styles}
+          />
+
+          {(hasAuth || info.spamScore || info.spamLLM) && (
+            <>
+              <Text style={styles.detailsSection}>{t('email_viewer.details.authentication_security', 'Authentication & security')}</Text>
+              <View style={styles.chips}>
+                {auth?.spf && <AuthChip label="SPF" result={auth.spf.result} styles={styles} c={c} />}
+                {auth?.dkim && <AuthChip label="DKIM" result={auth.dkim.result} styles={styles} c={c} />}
+                {auth?.dmarc && <AuthChip label="DMARC" result={auth.dmarc.result} styles={styles} c={c} />}
+                {auth?.iprev && <AuthChip label={t('email_viewer.details.iprev', 'Reverse DNS')} result={auth.iprev.result} styles={styles} c={c} />}
+              </View>
+              {spoofed && (
+                <Text style={[styles.detailValue, { color: c.error }]}>
+                  {t('email_viewer.authentication.spoof_warning', 'The sender address could not be verified - this message may be spoofed.')}
+                </Text>
+              )}
+              <DetailRow label={t('email_viewer.authentication.policy', 'Policy')} value={auth?.dmarc?.policy} styles={styles} />
+              <DetailRow
+                label={t('email_viewer.authentication.spam_score', 'Spam Score')}
+                value={info.spamScore ? `${info.spamScore.score} (${info.spamScore.status})` : undefined}
+                styles={styles}
+              />
+              <DetailRow
+                label={t('email_viewer.details.ai_verdict', 'AI verdict')}
+                value={info.spamLLM ? `${info.spamLLM.verdict} - ${info.spamLLM.explanation}` : undefined}
+                styles={styles}
+              />
+            </>
+          )}
+
+          <Text style={styles.detailsSection}>{t('email_viewer.details.identifiers_threading', 'Identifiers & threading')}</Text>
+          <DetailRow label={t('email_viewer.headers.message_id', 'Message ID')} value={info.messageId} styles={styles} mono />
+          <DetailRow label={t('email_viewer.details.in_reply_to', 'In-Reply-To')} value={email.inReplyTo?.join(', ')} styles={styles} mono />
+          <DetailRow label={t('email_viewer.details.references', 'References')} value={email.references?.length ? `${email.references.length}` : undefined} styles={styles} />
+          <DetailRow label={t('email_viewer.details.thread_id', 'Thread ID')} value={email.threadId} styles={styles} mono />
+
+          {(info.list.listId || info.list.listHelp || info.list.listPost || info.list.listUnsubscribe) && (
+            <>
+              <Text style={styles.detailsSection}>{t('email_viewer.details.mailing_list', 'Mailing list')}</Text>
+              <DetailRow label={t('email_viewer.details.list_id', 'List ID')} value={info.list.listId} styles={styles} mono />
+              <DetailRow label={t('email_viewer.details.list_help', 'List help')} value={info.list.listHelp} styles={styles} mono />
+              <DetailRow label={t('email_viewer.details.list_post', 'List post')} value={info.list.listPost} styles={styles} mono />
+              <DetailRow label={t('email_viewer.details.list_unsubscribe', 'Unsubscribe')} value={info.list.listUnsubscribe?.http ?? info.list.listUnsubscribe?.mailto} styles={styles} mono />
+            </>
+          )}
+
+          <Text style={styles.detailsSection}>{t('email_viewer.details.message_properties', 'Message properties')}</Text>
+          <DetailRow label={t('email_viewer.details.size', 'Size')} value={formatSize(email.size)} styles={styles} />
+          <DetailRow label={t('email_viewer.details.mime_type', 'MIME type')} value={email.bodyStructure?.type} styles={styles} mono />
+          <DetailRow label={t('email_viewer.attachments', 'Attachments')} value={attachmentsSummary} styles={styles} />
+        </View>
+      )}
+    </View>
+  );
+}
+
+function makeStyles(c: ThemePalette) {
+  return StyleSheet.create({
+    block: {
+      backgroundColor: c.background,
+      paddingHorizontal: spacing.lg,
+      paddingVertical: spacing.md,
+      gap: spacing.sm,
+    },
+    row: { flexDirection: 'row', alignItems: 'flex-start', gap: spacing.md },
+    info: { flex: 1, minWidth: 0 },
+    name: { ...typography.bodySemibold, color: c.text },
+    email: { ...typography.caption, color: c.textSecondary, marginTop: 2 },
+    recipients: { ...typography.caption, color: c.textSecondary, marginTop: 4 },
+    recipientsLabel: { color: c.textMuted },
+    recipientLink: { color: c.textSecondary },
+    meta: { alignItems: 'flex-end', paddingTop: 1, gap: 2 },
+    date: { ...typography.caption, color: c.textSecondary },
+    time: { ...typography.caption, color: c.textMuted },
+    star: { paddingTop: 4 },
+    badges: { flexDirection: 'row', flexWrap: 'wrap', gap: spacing.xs },
+    badge: {
+      flexDirection: 'row',
+      alignItems: 'center',
+      gap: 4,
+      paddingHorizontal: spacing.sm,
+      paddingVertical: 2,
+      borderRadius: radius.full,
+      backgroundColor: c.surfaceHover,
+    },
+    badgeDot: { width: 8, height: 8, borderRadius: 4 },
+    badgeText: { ...typography.small, color: c.textSecondary },
+    detailsToggle: { flexDirection: 'row', alignItems: 'center', gap: 4, alignSelf: 'flex-start' },
+    detailsToggleText: { ...typography.caption, color: c.primary, fontWeight: '600' },
+    details: {
+      backgroundColor: c.surface,
+      borderWidth: 1,
+      borderColor: c.border,
+      borderRadius: radius.md,
+      padding: spacing.md,
+      gap: spacing.xs,
+    },
+    detailsSection: { ...typography.small, color: c.textMuted, textTransform: 'uppercase', marginTop: spacing.xs, letterSpacing: 0.5 },
+    detailRow: { flexDirection: 'row', gap: spacing.sm },
+    detailLabel: { ...typography.caption, color: c.textMuted, width: 92 },
+    detailValue: { ...typography.caption, color: c.text, flex: 1 },
+    detailMono: { fontFamily: 'monospace', fontSize: 11 },
+    chips: { flexDirection: 'row', flexWrap: 'wrap', gap: spacing.xs, marginBottom: spacing.xs },
+    chip: {
+      flexDirection: 'row',
+      alignItems: 'center',
+      gap: 4,
+      paddingHorizontal: spacing.sm,
+      paddingVertical: 3,
+      borderRadius: radius.full,
+      borderWidth: 1,
+    },
+    chipText: { ...typography.small },
+  });
+}
diff --git a/src/components/email/QuickReplyBox.tsx b/src/components/email/QuickReplyBox.tsx
new file mode 100644
index 00000000..a761535f
--- /dev/null
+++ b/src/components/email/QuickReplyBox.tsx
@@ -0,0 +1,173 @@
+import React from 'react';
+import { View, Text, StyleSheet, TextInput, Pressable, ActivityIndicator, Alert } from 'react-native';
+import { Send, Maximize2 } from 'lucide-react-native';
+import type { Email } from '../../api/types';
+import { spacing, radius, typography, type ThemePalette } from '../../theme/tokens';
+import { useColors } from '../../theme/colors';
+import { useSettingsStore } from '../../stores/settings-store';
+import { useLocaleStore } from '../../stores/locale-store';
+import { useEmailStore } from '../../stores/email-store';
+import { sendEmail, patchKeywordsForEmails } from '../../api/email';
+import { buildReplyRecipients } from '../../lib/reply-recipients';
+import { buildReplySubject } from '../../lib/subject-prefix';
+import { computeReplyThreadingHeaders } from '../../lib/email-threading';
+import { findReceivingIdentity } from '../../lib/email-headers';
+import { plainTextBody } from '../../lib/email-body';
+import { htmlToPlainText } from '../../lib/compose-html';
+import { pickEmailBody } from '../../lib/email-body';
+import { mailboxesForSiblingOf } from '../../lib/mailbox-tree';
+import { emailDisplayDate, formatFullDateTime } from '../../lib/email-date';
+
+interface Props {
+  email: Email;
+  jmapAccountId?: string;
+  /** Open the full composer with the draft text carried over. */
+  onMoreOptions: (draft: string) => void;
+  /** Reflect `$answered` in the caller's cache. */
+  onSent?: (email: Email) => void;
+}
+
+/**
+ * Inline reply box under the message (webmail quick reply): plain-text reply
+ * to the sender with the original quoted, sent through the identity that
+ * received the message. "More options" hands the text to the full composer.
+ */
+export function QuickReplyBox({ email, jmapAccountId, onMoreOptions, onSent }: Props) {
+  const c = useColors();
+  const styles = React.useMemo(() => makeStyles(c), [c]);
+  const t = useLocaleStore((s) => s.t);
+  const locale = useLocaleStore((s) => s.locale);
+  const timeFormat = useSettingsStore((s) => s.timeFormat);
+  const identities = useSettingsStore((s) => s.identities);
+  const sendDelaySeconds = useSettingsStore((s) => s.sendDelaySeconds);
+  const mailboxes = useEmailStore((s) => s.mailboxes);
+  const currentMailboxId = useEmailStore((s) => s.currentMailboxId);
+  const [text, setText] = React.useState('');
+  const [sending, setSending] = React.useState(false);
+
+  React.useEffect(() => { setText(''); }, [email.id]);
+
+  const from = email.from?.[0];
+  if (!from?.email || email.keywords?.$draft) return null;
+
+  const send = async () => {
+    const body = text.trim();
+    if (!body || sending) return;
+    const identity = findReceivingIdentity(identities, email) ?? identities[0];
+    if (!identity) {
+      Alert.alert(t('common.error', 'Error'), t('email_viewer.unsubscribe_banner.no_identity', 'No sending identity available'));
+      return;
+    }
+    const scoped = mailboxesForSiblingOf(mailboxes, currentMailboxId);
+    const sent = scoped.find((m) => m.role === 'sent');
+    const drafts = scoped.find((m) => m.role === 'drafts');
+    if (!sent) {
+      Alert.alert(t('common.error', 'Error'), t('email_composer.no_sent_folder', 'No Sent folder found'));
+      return;
+    }
+    setSending(true);
+    try {
+      const ownEmails = identities.map((i) => i.email).filter(Boolean);
+      const recipients = buildReplyRecipients(
+        { from: email.from, replyToAddresses: email.replyTo, to: email.to, cc: email.cc },
+        'reply',
+        ownEmails,
+      );
+      const picked = pickEmailBody(email);
+      const original = picked.text ?? (picked.html ? htmlToPlainText(picked.html) : plainTextBody(email));
+      const quoted = original.split('\n').map((l) => `> ${l}`).join('\n');
+      const header = `${formatFullDateTime(emailDisplayDate(email), timeFormat, locale)}, ${from.name ? `${from.name} <${from.email}>` : from.email}:`;
+      const threading = computeReplyThreadingHeaders(email);
+      await sendEmail(
+        {
+          from: [{ name: identity.name, email: identity.email }],
+          to: recipients.to.filter((r) => !!r.email).map((r) => ({ email: r.email!, name: r.name })),
+          cc: recipients.cc.filter((r) => !!r.email).map((r) => ({ email: r.email!, name: r.name })),
+          subject: buildReplySubject(email.subject, t('email_composer.prefix.reply', 'Re:')),
+          textBody: `${body}\n\n${header}\n${quoted}`,
+          inReplyTo: threading?.inReplyTo,
+          references: threading?.references,
+        },
+        identity.id,
+        sent.originalId ?? sent.id,
+        sendDelaySeconds > 0 ? sendDelaySeconds : undefined,
+        { draftsMailboxId: drafts ? (drafts.originalId ?? drafts.id) : undefined, accountId: jmapAccountId },
+      );
+      try {
+        await patchKeywordsForEmails([email.id], { $answered: true }, jmapAccountId);
+      } catch { /* the reply is out; the flag is cosmetic */ }
+      onSent?.({ ...email, keywords: { ...email.keywords, $answered: true } });
+      setText('');
+    } catch (err) {
+      Alert.alert(t('email_composer.send_failed', 'Failed to send'), err instanceof Error ? err.message : String(err));
+    } finally {
+      setSending(false);
+    }
+  };
+
+  return (
+    <View style={styles.box}>
+      <TextInput
+        value={text}
+        onChangeText={setText}
+        placeholder={t('email_viewer.quick_reply_placeholder', 'Write a quick reply...')}
+        placeholderTextColor={c.textMuted}
+        style={styles.input}
+        multiline
+        editable={!sending}
+      />
+      <View style={styles.actions}>
+        <Pressable style={styles.more} onPress={() => onMoreOptions(text)} hitSlop={6}>
+          <Maximize2 size={14} color={c.textSecondary} />
+          <Text style={styles.moreText}>{t('email_viewer.more_options', 'More options')}</Text>
+        </Pressable>
+        <Pressable
+          style={[styles.send, (!text.trim() || sending) && styles.sendDisabled]}
+          onPress={send}
+          disabled={!text.trim() || sending}
+        >
+          {sending ? <ActivityIndicator size="small" color={c.primaryForeground} /> : <Send size={14} color={c.primaryForeground} />}
+          <Text style={styles.sendText}>{sending ? t('email_viewer.sending', 'Sending...') : t('email_viewer.send', 'Send')}</Text>
+        </Pressable>
+      </View>
+    </View>
+  );
+}
+
+function makeStyles(c: ThemePalette) {
+  return StyleSheet.create({
+    box: {
+      marginHorizontal: spacing.lg,
+      marginVertical: spacing.md,
+      borderWidth: 1,
+      borderColor: c.border,
+      borderRadius: radius.md,
+      backgroundColor: c.surface,
+      padding: spacing.sm,
+      gap: spacing.sm,
+    },
+    input: {
+      ...typography.body,
+      color: c.text,
+      minHeight: 44,
+      maxHeight: 160,
+      paddingHorizontal: spacing.sm,
+      paddingVertical: spacing.xs,
+      textAlignVertical: 'top',
+    },
+    actions: { flexDirection: 'row', alignItems: 'center', justifyContent: 'space-between' },
+    more: { flexDirection: 'row', alignItems: 'center', gap: 4, paddingVertical: 4 },
+    moreText: { ...typography.caption, color: c.textSecondary },
+    send: {
+      flexDirection: 'row',
+      alignItems: 'center',
+      gap: spacing.xs,
+      backgroundColor: c.primary,
+      paddingHorizontal: spacing.md,
+      paddingVertical: 6,
+      borderRadius: radius.full,
+    },
+    sendDisabled: { opacity: 0.5 },
+    sendText: { ...typography.caption, color: c.primaryForeground, fontWeight: '600' },
+  });
+}
diff --git a/src/components/email/ReadReceiptBanner.tsx b/src/components/email/ReadReceiptBanner.tsx
new file mode 100644
index 00000000..94baecd1
--- /dev/null
+++ b/src/components/email/ReadReceiptBanner.tsx
@@ -0,0 +1,163 @@
+import React from 'react';
+import { View, Text, StyleSheet, Pressable, ActivityIndicator, Alert } from 'react-native';
+import { MailCheck } from 'lucide-react-native';
+import type { Email } from '../../api/types';
+import { spacing, typography, type ThemePalette } from '../../theme/tokens';
+import { useColors } from '../../theme/colors';
+import { useLocaleStore } from '../../stores/locale-store';
+import { useSettingsStore } from '../../stores/settings-store';
+import { useEmailStore } from '../../stores/email-store';
+import { sendReadReceipt, patchKeywordsForEmails } from '../../api/email';
+import { findReceivingIdentity } from '../../lib/email-headers';
+import { mailboxesForSiblingOf } from '../../lib/mailbox-tree';
+
+interface Props {
+  email: Email;
+  /** Bare address from Disposition-Notification-To. */
+  requestedBy: string;
+  jmapAccountId?: string;
+  /** Role of the folder the message was opened from (receipts only in received folders). */
+  currentMailboxRole?: string | null;
+  /** Reflect `$mdnsent` in the caller's cache. */
+  onHandled: (email: Email) => void;
+}
+
+/**
+ * Read-receipt (MDN, RFC 8098) request banner: Send / Ignore, or auto-send
+ * in "always" mode. Either answer flags the message `$mdnsent` (RFC 3503) so
+ * the request is suppressed in every client, not just here. Never offered
+ * for the user's own copies, trash or spam.
+ */
+export function ReadReceiptBanner({ email, requestedBy, jmapAccountId, currentMailboxRole, onHandled }: Props) {
+  const c = useColors();
+  const styles = React.useMemo(() => makeStyles(c), [c]);
+  const t = useLocaleStore((s) => s.t);
+  const identities = useSettingsStore((s) => s.identities);
+  const fetchIdentities = useSettingsStore((s) => s.fetchIdentities);
+  const readReceiptResponse = useSettingsStore((s) => s.readReceiptResponse);
+  const mailboxes = useEmailStore((s) => s.mailboxes);
+  const currentMailboxId = useEmailStore((s) => s.currentMailboxId);
+  const [busy, setBusy] = React.useState(false);
+  const [handledLocally, setHandledLocally] = React.useState(false);
+  const autoRef = React.useRef<string | null>(null);
+
+  React.useEffect(() => { setHandledLocally(false); }, [email.id]);
+  React.useEffect(() => { if (identities.length === 0) void fetchIdentities(); }, [identities.length, fetchIdentities]);
+
+  const eligibleFolder = !['sent', 'drafts', 'trash', 'junk', 'spam'].includes(currentMailboxRole || '');
+  const identity = React.useMemo(() => findReceivingIdentity(identities, email), [identities, email]);
+  const shouldOffer =
+    !!requestedBy
+    && !email.keywords?.$mdnsent
+    && !email.keywords?.$draft
+    && !handledLocally
+    && readReceiptResponse !== 'never'
+    && eligibleFolder
+    && !!identity;
+
+  const flagSent = React.useCallback(async () => {
+    try {
+      await patchKeywordsForEmails([email.id], { $mdnsent: true }, jmapAccountId);
+    } catch { /* best effort - the local flag still hides the banner */ }
+    onHandled({ ...email, keywords: { ...email.keywords, $mdnsent: true } });
+  }, [email, jmapAccountId, onHandled]);
+
+  const send = React.useCallback(async (automatic: boolean) => {
+    if (!identity) return;
+    const scoped = mailboxesForSiblingOf(mailboxes, currentMailboxId);
+    const sent = scoped.find((m) => m.role === 'sent');
+    if (!sent) throw new Error(t('email_composer.no_sent_folder', 'No Sent folder found'));
+    await sendReadReceipt({
+      to: requestedBy,
+      fromEmail: identity.email,
+      fromName: identity.name,
+      identityId: identity.id,
+      sentMailboxId: sent.originalId ?? sent.id,
+      accountId: jmapAccountId,
+      originalMessageId: email.messageId,
+      originalSubject: email.subject,
+      originalRecipient: identity.email,
+      automatic,
+      subject: t('email_viewer.read_receipt.mdn_subject', 'Read: {subject}', { subject: email.subject || '' }),
+      humanText: t(
+        'email_viewer.read_receipt.mdn_body',
+        "This is a return receipt for the message you sent to {recipient}.\n\nNote: This receipt only acknowledges that the message was displayed on the recipient's device. There is no guarantee that the recipient has read or understood the message contents.",
+        { recipient: identity.email },
+      ),
+    });
+    await flagSent();
+  }, [identity, mailboxes, currentMailboxId, requestedBy, jmapAccountId, email.messageId, email.subject, t, flagSent]);
+
+  // "always" mode: auto-send once when the message is opened.
+  React.useEffect(() => {
+    if (readReceiptResponse !== 'always' || !shouldOffer) return;
+    if (autoRef.current === email.id) return;
+    autoRef.current = email.id;
+    setHandledLocally(true);
+    send(true).catch((err) => {
+      console.warn('[mdn] auto-send failed', err);
+      autoRef.current = null;
+    });
+  }, [readReceiptResponse, shouldOffer, email.id, send]);
+
+  if (!shouldOffer || readReceiptResponse === 'always') return null;
+
+  const onSend = async () => {
+    setBusy(true);
+    try {
+      await send(false);
+      setHandledLocally(true);
+    } catch (err) {
+      Alert.alert(
+        t('email_viewer.read_receipt.send_failed', 'Read receipt could not be sent'),
+        err instanceof Error ? err.message : String(err),
+      );
+    } finally {
+      setBusy(false);
+    }
+  };
+
+  const onIgnore = async () => {
+    setHandledLocally(true);
+    await flagSent();
+  };
+
+  return (
+    <View style={styles.banner}>
+      <MailCheck size={16} color={c.textSecondary} />
+      <Text style={styles.text}>{t('email_viewer.read_receipt.prompt', 'The sender asked to be notified when you open this message.')}</Text>
+      {busy ? (
+        <ActivityIndicator size="small" color={c.primary} />
+      ) : (
+        <View style={styles.actions}>
+          <Pressable onPress={onSend} hitSlop={8}>
+            <Text style={styles.primary}>{t('email_viewer.read_receipt.send', 'Send receipt')}</Text>
+          </Pressable>
+          <Pressable onPress={onIgnore} hitSlop={8}>
+            <Text style={styles.secondary}>{t('email_viewer.read_receipt.ignore', 'Ignore')}</Text>
+          </Pressable>
+        </View>
+      )}
+    </View>
+  );
+}
+
+function makeStyles(c: ThemePalette) {
+  return StyleSheet.create({
+    banner: {
+      flexDirection: 'row',
+      flexWrap: 'wrap',
+      alignItems: 'center',
+      gap: spacing.sm,
+      paddingHorizontal: spacing.lg,
+      paddingVertical: spacing.sm,
+      backgroundColor: c.surfaceHover,
+      borderBottomWidth: 1,
+      borderBottomColor: c.border,
+    },
+    text: { ...typography.caption, color: c.textSecondary, flex: 1, minWidth: 160 },
+    actions: { flexDirection: 'row', gap: spacing.md },
+    primary: { ...typography.caption, color: c.primary, fontWeight: '600' },
+    secondary: { ...typography.caption, color: c.textMuted, fontWeight: '600' },
+  });
+}
diff --git a/src/components/email/ThreadMessageCard.tsx b/src/components/email/ThreadMessageCard.tsx
new file mode 100644
index 00000000..4d9b7edc
--- /dev/null
+++ b/src/components/email/ThreadMessageCard.tsx
@@ -0,0 +1,127 @@
+import React from 'react';
+import { View, Text, StyleSheet, Pressable } from 'react-native';
+import { Paperclip, Reply, ReplyAll, Forward, Star } from 'lucide-react-native';
+import type { Email } from '../../api/types';
+import { spacing, radius, typography, componentSizes, type ThemePalette } from '../../theme/tokens';
+import { useColors } from '../../theme/colors';
+import { useSettingsStore } from '../../stores/settings-store';
+import { useLocaleStore } from '../../stores/locale-store';
+import SenderAvatar from '../SenderAvatar';
+import { MessageContent, type MessageContentProps } from './MessageContent';
+import { emailDisplayDate, formatHeaderDate, formatHeaderTime } from '../../lib/email-date';
+
+interface Props extends MessageContentProps {
+  expanded: boolean;
+  onToggleExpanded: () => void;
+  onReply: (mode: 'reply' | 'replyAll' | 'forward', email: Email) => void;
+}
+
+/**
+ * One message of a conversation: a collapsed summary row (sender, date,
+ * preview) that expands into the full message with its own reply / forward
+ * actions - the webmail's thread-conversation-view cards.
+ */
+export function ThreadMessageCard({ expanded, onToggleExpanded, onReply, ...content }: Props) {
+  const { email, onToggleStar } = content;
+  const c = useColors();
+  const styles = React.useMemo(() => makeStyles(c), [c]);
+  const t = useLocaleStore((s) => s.t);
+  const locale = useLocaleStore((s) => s.locale);
+  const timeFormat = useSettingsStore((s) => s.timeFormat);
+  const from = email.from?.[0];
+  const unread = !email.keywords?.$seen;
+  const starred = !!email.keywords?.$flagged;
+  const date = emailDisplayDate(email);
+
+  if (!expanded) {
+    return (
+      <Pressable onPress={onToggleExpanded} style={({ pressed }) => [styles.collapsed, pressed && styles.pressed]}>
+        <SenderAvatar name={from?.name} email={from?.email} size={componentSizes.avatarSm} />
+        <View style={styles.collapsedInfo}>
+          <View style={styles.collapsedTop}>
+            <Text style={[styles.collapsedName, unread && styles.unread]} numberOfLines={1}>
+              {from?.name || from?.email || t('email_viewer.unknown_sender', 'Unknown')}
+            </Text>
+            {email.hasAttachment && <Paperclip size={12} color={c.textMuted} />}
+            <Text style={styles.collapsedDate}>{formatHeaderDate(date, locale)} {formatHeaderTime(date, timeFormat, locale)}</Text>
+          </View>
+          <Text style={styles.collapsedPreview} numberOfLines={1}>{email.preview || ''}</Text>
+        </View>
+        {starred && <Star size={14} color={c.starred} fill={c.starred} />}
+      </Pressable>
+    );
+  }
+
+  return (
+    <View style={styles.expanded}>
+      <Pressable onPress={onToggleExpanded} style={styles.collapseHandle} hitSlop={6} accessibilityLabel={t('threads.collapse', 'Collapse conversation')} />
+      <MessageContent {...content} compact={false} onToggleStar={onToggleStar} />
+      <View style={styles.actions}>
+        <Pressable style={styles.actionBtn} onPress={() => onReply('reply', email)} hitSlop={4}>
+          <Reply size={16} color={c.textSecondary} />
+          <Text style={styles.actionLabel}>{t('email_viewer.reply', 'Reply')}</Text>
+        </Pressable>
+        <Pressable style={styles.actionBtn} onPress={() => onReply('replyAll', email)} hitSlop={4}>
+          <ReplyAll size={16} color={c.textSecondary} />
+          <Text style={styles.actionLabel}>{t('email_viewer.reply_all', 'Reply All')}</Text>
+        </Pressable>
+        <Pressable style={styles.actionBtn} onPress={() => onReply('forward', email)} hitSlop={4}>
+          <Forward size={16} color={c.textSecondary} />
+          <Text style={styles.actionLabel}>{t('email_viewer.forward', 'Forward')}</Text>
+        </Pressable>
+      </View>
+    </View>
+  );
+}
+
+function makeStyles(c: ThemePalette) {
+  return StyleSheet.create({
+    collapsed: {
+      flexDirection: 'row',
+      alignItems: 'center',
+      gap: spacing.md,
+      paddingHorizontal: spacing.lg,
+      paddingVertical: spacing.md,
+      backgroundColor: c.surface,
+      borderBottomWidth: 1,
+      borderBottomColor: c.border,
+    },
+    pressed: { backgroundColor: c.surfaceHover },
+    collapsedInfo: { flex: 1, minWidth: 0 },
+    collapsedTop: { flexDirection: 'row', alignItems: 'center', gap: spacing.xs },
+    collapsedName: { ...typography.body, color: c.text, flex: 1 },
+    unread: { fontWeight: '700' },
+    collapsedDate: { ...typography.small, color: c.textMuted },
+    collapsedPreview: { ...typography.caption, color: c.textMuted, marginTop: 2 },
+    expanded: {
+      backgroundColor: c.background,
+      borderBottomWidth: 1,
+      borderBottomColor: c.border,
+    },
+    collapseHandle: {
+      height: 6,
+      backgroundColor: c.surfaceHover,
+      borderRadius: radius.xs,
+    },
+    actions: {
+      flexDirection: 'row',
+      gap: spacing.sm,
+      paddingHorizontal: spacing.lg,
+      paddingVertical: spacing.sm,
+      borderTopWidth: 1,
+      borderTopColor: c.border,
+    },
+    actionBtn: {
+      flexDirection: 'row',
+      alignItems: 'center',
+      gap: spacing.xs,
+      paddingHorizontal: spacing.md,
+      paddingVertical: 6,
+      borderRadius: radius.full,
+      borderWidth: 1,
+      borderColor: c.border,
+      backgroundColor: c.surface,
+    },
+    actionLabel: { ...typography.caption, color: c.textSecondary },
+  });
+}
diff --git a/src/components/email/UnsubscribeBanner.tsx b/src/components/email/UnsubscribeBanner.tsx
new file mode 100644
index 00000000..66c87aa0
--- /dev/null
+++ b/src/components/email/UnsubscribeBanner.tsx
@@ -0,0 +1,195 @@
+import React from 'react';
+import { View, Text, StyleSheet, Pressable, ActivityIndicator, Alert } from 'react-native';
+import AsyncStorage from '@react-native-async-storage/async-storage';
+import * as WebBrowser from 'expo-web-browser';
+import { MailMinus, CheckCircle2, AlertCircle, X } from 'lucide-react-native';
+import type { Email } from '../../api/types';
+import { spacing, radius, typography, type ThemePalette } from '../../theme/tokens';
+import { useColors } from '../../theme/colors';
+import { useLocaleStore } from '../../stores/locale-store';
+import { useSettingsStore } from '../../stores/settings-store';
+import { useEmailStore } from '../../stores/email-store';
+import { sendEmail } from '../../api/email';
+import { isValidUnsubscribeUrl, parseMailtoUrl, isOneClickUnsubscribe } from '../../lib/unsubscribe';
+import type { ListHeaders } from '../../lib/email-headers';
+import { findReceivingIdentity } from '../../lib/email-headers';
+import { mailboxesForSiblingOf } from '../../lib/mailbox-tree';
+
+const DISMISSED_KEY = 'webmail:unsubscribe-dismissed:v1';
+const dismissed = new Set<string>();
+let dismissedLoaded: Promise<void> | null = null;
+
+function loadDismissed(): Promise<void> {
+  if (!dismissedLoaded) {
+    dismissedLoaded = AsyncStorage.getItem(DISMISSED_KEY)
+      .then((raw) => {
+        if (!raw) return;
+        for (const id of JSON.parse(raw) as string[]) dismissed.add(id);
+      })
+      .catch(() => undefined);
+  }
+  return dismissedLoaded;
+}
+
+function persistDismissed(): void {
+  // Keep the list bounded - the newest few hundred Message-IDs are plenty.
+  const list = Array.from(dismissed).slice(-500);
+  void AsyncStorage.setItem(DISMISSED_KEY, JSON.stringify(list)).catch(() => undefined);
+}
+
+interface Props {
+  email: Email;
+  list: ListHeaders;
+  /** Dedupe key for dismissals (bare Message-ID, else the JMAP id). */
+  messageKey: string;
+  jmapAccountId?: string;
+}
+
+/**
+ * List-Unsubscribe (RFC 2369 / RFC 8058) banner. An https one-click URL is
+ * POSTed directly; a plain http(s) URL opens in the in-app browser; a
+ * mailto: URL is sent through the account itself (handing it to the OS mail
+ * app goes nowhere for most users). Dismissals are remembered per Message-ID.
+ */
+export function UnsubscribeBanner({ email, list, messageKey, jmapAccountId }: Props) {
+  const c = useColors();
+  const styles = React.useMemo(() => makeStyles(c), [c]);
+  const t = useLocaleStore((s) => s.t);
+  const identities = useSettingsStore((s) => s.identities);
+  const mailboxes = useEmailStore((s) => s.mailboxes);
+  const currentMailboxId = useEmailStore((s) => s.currentMailboxId);
+  const [hidden, setHidden] = React.useState(true);
+  const [state, setState] = React.useState<'idle' | 'busy' | 'done' | 'error'>('idle');
+
+  const unsub = list.listUnsubscribe;
+  const method = unsub?.preferred;
+  const url = method === 'http' ? unsub?.http : unsub?.mailto;
+
+  React.useEffect(() => {
+    let cancelled = false;
+    setState('idle');
+    void loadDismissed().then(() => {
+      if (!cancelled) setHidden(dismissed.has(messageKey));
+    });
+    return () => { cancelled = true; };
+  }, [messageKey]);
+
+  if (hidden || !url || !method) return null;
+
+  const dismiss = () => {
+    dismissed.add(messageKey);
+    persistDismissed();
+    setHidden(true);
+  };
+
+  const perform = async () => {
+    if (!isValidUnsubscribeUrl(url)) { setState('error'); return; }
+    setState('busy');
+    try {
+      if (method === 'http') {
+        if (isOneClickUnsubscribe(list.listUnsubscribePost, url)) {
+          const res = await fetch(url, {
+            method: 'POST',
+            headers: { 'Content-Type': 'application/x-www-form-urlencoded' },
+            body: 'List-Unsubscribe=One-Click',
+          });
+          if (!res.ok) throw new Error(`HTTP ${res.status}`);
+        } else {
+          await WebBrowser.openBrowserAsync(url);
+        }
+      } else {
+        const fields = parseMailtoUrl(url);
+        if (!fields) throw new Error('invalid mailto');
+        const identity = findReceivingIdentity(identities, email) ?? identities[0];
+        if (!identity) throw new Error(t('email_viewer.unsubscribe_banner.no_identity', 'No sending identity available'));
+        const scoped = mailboxesForSiblingOf(mailboxes, currentMailboxId);
+        const sent = scoped.find((m) => m.role === 'sent');
+        const drafts = scoped.find((m) => m.role === 'drafts');
+        if (!sent) throw new Error(t('email_composer.no_sent_folder', 'No Sent folder found'));
+        await sendEmail(
+          {
+            from: [{ name: identity.name, email: identity.email }],
+            to: fields.to.map((address) => ({ email: address })),
+            cc: fields.cc?.map((address) => ({ email: address })),
+            subject: fields.subject ?? '',
+            textBody: fields.body ?? '',
+          },
+          identity.id,
+          sent.originalId ?? sent.id,
+          undefined,
+          { draftsMailboxId: drafts ? (drafts.originalId ?? drafts.id) : undefined, accountId: jmapAccountId },
+        );
+      }
+      setState('done');
+      setTimeout(dismiss, 3000);
+    } catch (err) {
+      console.warn('[unsubscribe] failed', err);
+      setState('error');
+    }
+  };
+
+  const confirm = () => {
+    Alert.alert(
+      t('email_viewer.unsubscribe_banner.confirm_title', 'Unsubscribe from this sender?'),
+      method === 'http'
+        ? t('email_viewer.unsubscribe_banner.confirm_message_http', 'The unsubscribe page will open in a new tab.')
+        : t('email_viewer.unsubscribe_banner.confirm_message_mailto', 'An unsubscribe email will be sent to the sender.'),
+      [
+        { text: t('email_viewer.unsubscribe_banner.cancel', 'Cancel'), style: 'cancel' },
+        { text: t('email_viewer.unsubscribe_banner.confirm_button', 'Confirm'), onPress: () => { void perform(); } },
+      ],
+    );
+  };
+
+  return (
+    <View style={styles.banner}>
+      <MailMinus size={14} color={c.textSecondary} />
+      <Text style={styles.label}>{t('email_viewer.unsubscribe_banner.label', 'Newsletter')}</Text>
+      {state === 'busy' ? (
+        <ActivityIndicator size="small" color={c.primary} />
+      ) : state === 'done' ? (
+        <View style={styles.status}>
+          <CheckCircle2 size={14} color={c.success} />
+          <Text style={[styles.statusText, { color: c.success }]}>
+            {t(method === 'http' ? 'email_viewer.unsubscribe_banner.success_http' : 'email_viewer.unsubscribe_banner.success_mailto',
+              method === 'http' ? 'Unsubscribe page opened' : 'Unsubscribe email sent')}
+          </Text>
+        </View>
+      ) : state === 'error' ? (
+        <View style={styles.status}>
+          <AlertCircle size={14} color={c.error} />
+          <Text style={[styles.statusText, { color: c.error }]}>{t('email_viewer.unsubscribe_banner.error', 'Unable to unsubscribe')}</Text>
+        </View>
+      ) : (
+        <Pressable onPress={confirm} hitSlop={8}>
+          <Text style={styles.action}>{t('email_viewer.unsubscribe_banner.button', 'Unsubscribe')}</Text>
+        </Pressable>
+      )}
+      <View style={styles.spacer} />
+      <Pressable onPress={dismiss} hitSlop={8} accessibilityLabel={t('email_viewer.unsubscribe_banner.dismiss', 'Dismiss')}>
+        <X size={16} color={c.textMuted} />
+      </Pressable>
+    </View>
+  );
+}
+
+function makeStyles(c: ThemePalette) {
+  return StyleSheet.create({
+    banner: {
+      flexDirection: 'row',
+      alignItems: 'center',
+      gap: spacing.sm,
+      paddingHorizontal: spacing.lg,
+      paddingVertical: spacing.sm,
+      backgroundColor: c.surfaceHover,
+      borderBottomWidth: 1,
+      borderBottomColor: c.border,
+      borderRadius: radius.xs,
+    },
+    label: { ...typography.caption, color: c.textSecondary },
+    action: { ...typography.caption, color: c.primary, fontWeight: '600' },
+    status: { flexDirection: 'row', alignItems: 'center', gap: 4 },
+    statusText: { ...typography.caption },
+    spacer: { flex: 1 },
+  });
+}
diff --git a/src/components/email/use-body-override.ts b/src/components/email/use-body-override.ts
new file mode 100644
index 00000000..ca16c9fa
--- /dev/null
+++ b/src/components/email/use-body-override.ts
@@ -0,0 +1,137 @@
+import React from 'react';
+import type { Attachment, Email } from '../../api/types';
+import { pickEmailBody } from '../../lib/email-body';
+import { fetchBlobBytes, bytesToBase64 } from '../../lib/email-export';
+import { isRfc822Attachment, isTnefAttachment } from '../../lib/attachment-display';
+import { parseTnef } from '../../lib/tnef';
+import { sniffImageMime } from '../../lib/email-html';
+
+/** A part extracted client-side (TNEF / embedded message) - bytes, not a blob. */
+export interface ExtractedAttachment {
+  name: string;
+  type: string;
+  size: number;
+  bytes: Uint8Array;
+}
+
+export interface BodyOverrideState {
+  /** Body to render instead of the message's own, when one was extracted. */
+  override: { html?: string | null; text?: string | null } | null;
+  /** Extra chips for extracted parts. */
+  extracted: ExtractedAttachment[];
+  /** winmail.dat was unpacked (its chip is hidden). */
+  tnefUnpacked: boolean;
+  loading: boolean;
+}
+
+const EMPTY: BodyOverrideState = { override: null, extracted: [], tnefUnpacked: false, loading: false };
+const MAX_UNWRAP_BYTES = 25 * 1024 * 1024;
+
+function toBytes(content: ArrayBuffer | Uint8Array | string): Uint8Array {
+  if (typeof content === 'string') return new TextEncoder().encode(content);
+  return content instanceof Uint8Array ? content : new Uint8Array(content);
+}
+
+/**
+ * Parse an embedded message/rfc822 part with postal-mime and inline its cid
+ * images as data: URIs (they are not JMAP blobs, so the body view can't
+ * fetch them).
+ */
+export async function unwrapEmbeddedMessage(bytes: Uint8Array): Promise<{
+  html: string | null;
+  text: string | null;
+  attachments: ExtractedAttachment[];
+}> {
+  const { default: PostalMime } = await import('postal-mime');
+  const parsed = await PostalMime.parse(bytes, { attachmentEncoding: 'arraybuffer' });
+  let html = parsed.html ?? null;
+  const text = parsed.text ?? null;
+  const attachments: ExtractedAttachment[] = [];
+  for (const att of parsed.attachments ?? []) {
+    const data = toBytes(att.content);
+    const cid = att.contentId?.replace(/^<|>$/g, '');
+    if (cid && html && html.includes(`cid:${cid}`)) {
+      const mime = sniffImageMime(data, att.mimeType);
+      html = html.split(`cid:${cid}`).join(`data:${mime};base64,${bytesToBase64(data)}`);
+      if (att.disposition === 'inline') continue;
+    }
+    attachments.push({
+      name: att.filename || 'attachment',
+      type: att.mimeType || 'application/octet-stream',
+      size: data.byteLength,
+      bytes: data,
+    });
+  }
+  return { html, text, attachments };
+}
+
+/**
+ * Two client-side unwraps the webmail does before rendering:
+ *  - Outlook "forward as attachment": the outer message is an empty envelope
+ *    around a message/rfc822 part - render the embedded message's body and
+ *    list its attachments (the .eml chip stays, it is a real attachment);
+ *  - TNEF winmail.dat: parse the container for the body and the files inside
+ *    it, and hide the opaque winmail.dat chip.
+ */
+export function useBodyOverride(email: Email, jmapAccountId?: string): BodyOverrideState {
+  const [state, setState] = React.useState<BodyOverrideState>(EMPTY);
+
+  const picked = React.useMemo(() => pickEmailBody(email), [email]);
+  const bodyEmpty = !picked.html && !(picked.text && picked.text.trim());
+  const rfc822 = React.useMemo(
+    () => (bodyEmpty ? (email.attachments ?? []).find((a): a is Attachment => isRfc822Attachment(a)) : undefined),
+    [email.attachments, bodyEmpty],
+  );
+  const tnef = React.useMemo(
+    () => (email.attachments ?? []).find((a) => isTnefAttachment(a.name, a.type)),
+    [email.attachments],
+  );
+
+  React.useEffect(() => {
+    let cancelled = false;
+    if (!rfc822 && !tnef) {
+      setState(EMPTY);
+      return;
+    }
+    setState({ ...EMPTY, loading: true });
+    void (async () => {
+      try {
+        if (tnef) {
+          if ((tnef.size ?? 0) > MAX_UNWRAP_BYTES) throw new Error('winmail.dat too large');
+          const bytes = await fetchBlobBytes(tnef.blobId, tnef.name, tnef.type, jmapAccountId);
+          const res = parseTnef(bytes);
+          if (cancelled) return;
+          const extracted = res.attachments.map((a) => ({
+            name: a.name, type: a.mimeType, size: a.data.byteLength, bytes: a.data,
+          }));
+          const unpacked = !!(res.htmlBody || res.body || extracted.length);
+          setState({
+            override: bodyEmpty && (res.htmlBody || res.body) ? { html: res.htmlBody, text: res.body } : null,
+            extracted,
+            tnefUnpacked: unpacked,
+            loading: false,
+          });
+          return;
+        }
+        if (rfc822) {
+          if ((rfc822.size ?? 0) > MAX_UNWRAP_BYTES) throw new Error('embedded message too large');
+          const bytes = await fetchBlobBytes(rfc822.blobId, rfc822.name, rfc822.type, jmapAccountId);
+          const res = await unwrapEmbeddedMessage(bytes);
+          if (cancelled) return;
+          setState({
+            override: res.html || res.text ? { html: res.html, text: res.text } : null,
+            extracted: res.attachments,
+            tnefUnpacked: false,
+            loading: false,
+          });
+        }
+      } catch (err) {
+        console.warn('[reader] body unwrap failed', err);
+        if (!cancelled) setState(EMPTY);
+      }
+    })();
+    return () => { cancelled = true; };
+  }, [rfc822, tnef, bodyEmpty, jmapAccountId]);
+
+  return state;
+}
diff --git a/src/lib/__tests__/attachment-display.test.ts b/src/lib/__tests__/attachment-display.test.ts
new file mode 100644
index 00000000..f56a1460
--- /dev/null
+++ b/src/lib/__tests__/attachment-display.test.ts
@@ -0,0 +1,75 @@
+import { describe, it, expect } from 'vitest';
+import {
+  getAttachmentDisplayName, visibleAttachments, previewKindFor, isReportPart, isRfc822Attachment,
+} from '../attachment-display';
+import { buildForwardAsAttachmentPayload } from '../forward-as-attachment';
+import type { Email } from '../../api/types';
+
+describe('getAttachmentDisplayName', () => {
+  it('uses the name, else a MIME-derived label', () => {
+    expect(getAttachmentDisplayName('a.pdf', 'application/pdf')).toBe('a.pdf');
+    expect(getAttachmentDisplayName(null, 'application/pdf')).toBe('Document.pdf');
+    expect(getAttachmentDisplayName(undefined, 'message/rfc822')).toBe('Email.eml');
+    expect(getAttachmentDisplayName(undefined, 'application/x-foo')).toBe('Attachment.foo');
+    expect(getAttachmentDisplayName(undefined, undefined)).toBe('Attachment');
+  });
+});
+
+describe('visibleAttachments', () => {
+  const email = {
+    attachments: [
+      { blobId: '1', type: 'image/png', name: 'logo.png', cid: 'logo', disposition: 'inline' },
+      { blobId: '2', type: 'image/png', name: 'photo.png', cid: 'photo', disposition: 'attachment' },
+      { blobId: '3', type: 'message/disposition-notification', name: undefined },
+      { blobId: '4', type: 'text/calendar', name: 'invite.ics' },
+      { blobId: '5', type: 'application/ms-tnef', name: 'winmail.dat' },
+      { blobId: '6', type: 'application/pdf', name: 'doc.pdf' },
+    ],
+  };
+
+  it('hides only inline-disposition cid images, report parts, shown calendar parts and unpacked TNEF', () => {
+    const shown = visibleAttachments(email, { hideInlineImageAttachments: true, calendarBannerShown: true, tnefUnpacked: true });
+    expect(shown.map((a) => a.blobId)).toEqual(['2', '6']);
+  });
+
+  it('keeps calendar parts and inline images when asked', () => {
+    const shown = visibleAttachments(email, { hideInlineImageAttachments: false, calendarBannerShown: false });
+    expect(shown.map((a) => a.blobId)).toEqual(['1', '2', '4', '5', '6']);
+  });
+});
+
+describe('previewKindFor / classification', () => {
+  it('classifies previewable types and refuses script-bearing ones', () => {
+    expect(previewKindFor({ type: 'image/jpeg', name: 'a.jpg' })).toBe('image');
+    expect(previewKindFor({ type: 'application/pdf', name: 'a.pdf' })).toBe('pdf');
+    expect(previewKindFor({ type: 'text/plain', name: 'a.txt' })).toBe('text');
+    expect(previewKindFor({ type: 'application/octet-stream', name: 'notes.md' })).toBe('text');
+    expect(previewKindFor({ type: 'message/rfc822', name: 'fwd.eml' })).toBe('eml');
+    expect(previewKindFor({ type: 'text/html', name: 'a.html' })).toBe('none');
+    expect(previewKindFor({ type: 'image/svg+xml', name: 'a.svg' })).toBe('none');
+    expect(previewKindFor({ type: 'application/zip', name: 'a.zip' })).toBe('none');
+    expect(isReportPart('message/delivery-status')).toBe(true);
+    expect(isRfc822Attachment({ type: 'application/octet-stream', name: 'x.eml' })).toBe(true);
+  });
+});
+
+describe('buildForwardAsAttachmentPayload', () => {
+  const email = {
+    id: 'e1', threadId: 't1', mailboxIds: {}, keywords: {}, size: 1234,
+    receivedAt: '2026-03-04T10:00:00Z', subject: 'Invoice', blobId: 'blob-1', hasAttachment: false,
+    from: [{ email: 'a@b.co', name: 'A' }], to: [{ email: 'me@x.co' }],
+  } as Email;
+
+  it('references the blob with a {date}-{subject}.eml name and a Fwd: subject', () => {
+    const p = buildForwardAsAttachmentPayload(email, 'Fwd:', { template: '{from}-{to}', lowercase: true });
+    expect(p?.subject).toBe('Fwd: Invoice');
+    expect(p?.attachment).toMatchObject({ blobId: 'blob-1', type: 'message/rfc822', size: 1234 });
+    expect(p?.attachment.name).toMatch(/^2026-03-04.*-invoice\.eml$/);
+    expect(p?.attachment.name).not.toContain('a@b.co');
+  });
+
+  it('returns null without a blob and leaves an empty subject alone', () => {
+    expect(buildForwardAsAttachmentPayload({ ...email, blobId: undefined }, 'Fwd:')).toBeNull();
+    expect(buildForwardAsAttachmentPayload({ ...email, subject: undefined }, 'Fwd:')?.subject).toBe('');
+  });
+});
diff --git a/src/lib/__tests__/email-date.test.ts b/src/lib/__tests__/email-date.test.ts
new file mode 100644
index 00000000..ab2255a7
--- /dev/null
+++ b/src/lib/__tests__/email-date.test.ts
@@ -0,0 +1,27 @@
+import { describe, it, expect } from 'vitest';
+import { emailDisplayDate, formatHeaderTime, MAX_FUTURE_SENT_AT_MS } from '../email-date';
+
+describe('emailDisplayDate', () => {
+  it('prefers sentAt over receivedAt (#891)', () => {
+    expect(emailDisplayDate({ sentAt: '2024-01-01T00:00:00Z', receivedAt: '2026-06-01T00:00:00Z' })).toBe('2024-01-01T00:00:00Z');
+  });
+
+  it('falls back when sentAt is missing, unparsable or forged into the future', () => {
+    expect(emailDisplayDate({ receivedAt: '2026-06-01T00:00:00Z' })).toBe('2026-06-01T00:00:00Z');
+    expect(emailDisplayDate({ sentAt: 'garbage', receivedAt: '2026-06-01T00:00:00Z' })).toBe('2026-06-01T00:00:00Z');
+    const received = Date.parse('2026-06-01T00:00:00Z');
+    const future = new Date(received + MAX_FUTURE_SENT_AT_MS + 1000).toISOString();
+    expect(emailDisplayDate({ sentAt: future, receivedAt: '2026-06-01T00:00:00Z' })).toBe('2026-06-01T00:00:00Z');
+    const slightlyAhead = new Date(received + 60_000).toISOString();
+    expect(emailDisplayDate({ sentAt: slightlyAhead, receivedAt: '2026-06-01T00:00:00Z' })).toBe(slightlyAhead);
+  });
+});
+
+describe('formatHeaderTime', () => {
+  it('honours the time-format setting', () => {
+    const iso = '2026-06-01T15:07:00';
+    expect(formatHeaderTime(iso, '24h', 'en')).toMatch(/15:07/);
+    expect(formatHeaderTime(iso, '12h', 'en')).toMatch(/3:07\s?PM/i);
+    expect(formatHeaderTime(undefined, '24h')).toBe('');
+  });
+});
diff --git a/src/lib/__tests__/email-headers.test.ts b/src/lib/__tests__/email-headers.test.ts
new file mode 100644
index 00000000..c166bb10
--- /dev/null
+++ b/src/lib/__tests__/email-headers.test.ts
@@ -0,0 +1,110 @@
+import { describe, it, expect } from 'vitest';
+import {
+  parseAuthenticationResults, parseSpamScore, parseSpamLLM, extractListHeaders,
+  isAuthenticationSpoofed, headersToRecord, deriveHeaderInfo, deliveryDeltaMs, formatDelta,
+  findReceivingIdentity,
+} from '../email-headers';
+
+describe('parseAuthenticationResults', () => {
+  it('parses spf/dkim/dmarc/iprev', () => {
+    const r = parseAuthenticationResults(
+      'mx.example; spf=pass smtp.mailfrom=news.example; dkim=pass header.d=news.example header.s=s1; dmarc=pass header.from=news.example policy.dmarc=none; iprev=pass policy.iprev=1.2.3.4',
+    );
+    expect(r.spf).toEqual({ result: 'pass', domain: 'news.example' });
+    expect(r.dkim).toEqual({ result: 'pass', domain: 'news.example', selector: 's1' });
+    expect(r.dmarc).toEqual({ result: 'pass', domain: 'news.example', policy: 'none' });
+    expect(r.iprev).toEqual({ result: 'pass', ip: '1.2.3.4' });
+  });
+
+  it('escalates a HELO hard fail over a MAIL FROM pass, but not a HELO none (#650)', () => {
+    const fail = parseAuthenticationResults('spf=pass smtp.mailfrom=a.example; spf=fail smtp.helo=b.example');
+    expect(fail.spf?.result).toBe('fail');
+    expect(fail.spf?.all).toHaveLength(2);
+    const none = parseAuthenticationResults('spf=pass smtp.mailfrom=a.example; spf=none smtp.helo=b.example');
+    expect(none.spf?.result).toBe('pass');
+  });
+});
+
+describe('isAuthenticationSpoofed', () => {
+  it('flags dmarc fail and spf fail without dkim', () => {
+    expect(isAuthenticationSpoofed({ dmarc: { result: 'fail' } })).toBe(true);
+    expect(isAuthenticationSpoofed({ spf: { result: 'fail' } })).toBe(true);
+    expect(isAuthenticationSpoofed({ spf: { result: 'fail' }, dkim: { result: 'pass' } })).toBe(false);
+    expect(isAuthenticationSpoofed(undefined)).toBe(false);
+  });
+});
+
+describe('parseSpamScore / parseSpamLLM', () => {
+  it('reads Stalwart and SpamAssassin formats', () => {
+    expect(parseSpamScore('ham, score=-0.25')).toEqual({ status: 'ham', score: -0.25 });
+    expect(parseSpamScore('No, score=1.5 required=5.0')).toEqual({ status: 'no', score: 1.5 });
+    expect(parseSpamScore('score: 7.2')).toEqual({ status: 'spam', score: 7.2 });
+    expect(parseSpamScore('nonsense')).toBeNull();
+    expect(parseSpamLLM(' LEGITIMATE (Looks like a receipt) ')).toEqual({ verdict: 'LEGITIMATE', explanation: 'Looks like a receipt' });
+    expect(parseSpamLLM('???')).toBeNull();
+  });
+});
+
+describe('extractListHeaders / headersToRecord', () => {
+  it('collects list headers case-insensitively', () => {
+    const rec = headersToRecord([
+      { name: 'List-ID', value: '<news.list.example>' },
+      { name: 'list-unsubscribe', value: '<mailto:u@list.example>, <https://list.example/u>' },
+      { name: 'List-Unsubscribe-Post', value: 'List-Unsubscribe=One-Click' },
+      { name: 'Received', value: 'a' },
+      { name: 'Received', value: 'b' },
+    ]);
+    expect(rec.Received).toEqual(['a', 'b']);
+    const list = extractListHeaders(rec);
+    expect(list.listId).toBe('<news.list.example>');
+    expect(list.listUnsubscribe?.preferred).toBe('http');
+    expect(list.listUnsubscribePost).toBe('List-Unsubscribe=One-Click');
+  });
+});
+
+describe('deriveHeaderInfo', () => {
+  it('pulls the receipt request, message id and spam score out of raw headers', () => {
+    const info = deriveHeaderInfo({
+      headers: [
+        { name: 'Disposition-Notification-To', value: 'Sender <s@x.example>' },
+        { name: 'X-Spam-Status', value: 'No, score=0.1' },
+        { name: 'Authentication-Results', value: 'mx; dmarc=fail header.from=x.example' },
+      ],
+      messageId: ['abc@x.example'],
+    });
+    expect(info.readReceiptRequestedBy).toBe('s@x.example');
+    expect(info.messageId).toBe('abc@x.example');
+    expect(info.spamScore?.score).toBe(0.1);
+    expect(isAuthenticationSpoofed(info.auth)).toBe(true);
+  });
+
+  it('copes with no headers', () => {
+    const info = deriveHeaderInfo({ headers: undefined, messageId: null });
+    expect(info.readReceiptRequestedBy).toBeNull();
+    expect(info.auth).toBeUndefined();
+    expect(info.list).toEqual({});
+  });
+});
+
+describe('deliveryDeltaMs / formatDelta', () => {
+  it('computes the routing delta and formats it', () => {
+    expect(deliveryDeltaMs({ sentAt: '2026-01-01T10:00:00Z', receivedAt: '2026-01-01T12:05:00Z' })).toBe(125 * 60000);
+    expect(deliveryDeltaMs({ sentAt: undefined, receivedAt: '2026-01-01T12:05:00Z' })).toBeNull();
+    expect(formatDelta(125 * 60000)).toBe('2 h 5 min');
+    expect(formatDelta(30 * 1000)).toBe('1 min');
+    expect(formatDelta(26 * 3600000)).toBe('1 d 2 h');
+  });
+});
+
+describe('findReceivingIdentity', () => {
+  const ids = [
+    { id: 'a', name: 'A', email: 'a@x.example', mayDelete: true },
+    { id: 'b', name: 'B', email: 'b@x.example', mayDelete: true },
+  ];
+  it('matches exact and +tag recipients, else the first identity', () => {
+    expect(findReceivingIdentity(ids, { to: [{ email: 'b@x.example' }] })?.id).toBe('b');
+    expect(findReceivingIdentity(ids, { cc: [{ email: 'b+news@x.example' }] })?.id).toBe('b');
+    expect(findReceivingIdentity(ids, { to: [{ email: 'other@y.example' }] })?.id).toBe('a');
+    expect(findReceivingIdentity([], { to: [] })).toBeUndefined();
+  });
+});
diff --git a/src/lib/__tests__/mdn.test.ts b/src/lib/__tests__/mdn.test.ts
new file mode 100644
index 00000000..0256b727
--- /dev/null
+++ b/src/lib/__tests__/mdn.test.ts
@@ -0,0 +1,49 @@
+import { describe, it, expect } from 'vitest';
+import { buildMdnMessage, encodeHeaderWord, rfc5322Date } from '../mdn';
+
+describe('buildMdnMessage', () => {
+  it('builds a two-part multipart/report with CRLF line endings', () => {
+    const raw = buildMdnMessage({
+      to: 'sender@remote.example',
+      fromEmail: 'me@x.example',
+      fromName: 'Me',
+      originalMessageId: ['orig@remote.example'],
+      originalSubject: 'Hello',
+      originalRecipient: 'me@x.example',
+      automatic: false,
+    });
+    expect(raw).toContain('From: Me <me@x.example>\r\n');
+    expect(raw).toContain('To: sender@remote.example\r\n');
+    expect(raw).toContain('Subject: Read: Hello\r\n');
+    expect(raw).toContain('In-Reply-To: <orig@remote.example>\r\n');
+    expect(raw).toContain('Content-Type: multipart/report; report-type=disposition-notification;');
+    expect(raw).toContain('Content-Type: message/disposition-notification\r\n');
+    expect(raw).toContain('Original-Message-ID: <orig@remote.example>\r\n');
+    expect(raw).toContain('Final-Recipient: rfc822;me@x.example\r\n');
+    expect(raw).toContain('Disposition: manual-action/MDN-sent-manually; displayed\r\n');
+    expect(raw.split('\n').every((l) => l === '' || l.endsWith('\r'))).toBe(true);
+  });
+
+  it('marks automatic receipts and encodes non-ASCII headers', () => {
+    const raw = buildMdnMessage({
+      to: 'a@b.example',
+      fromEmail: 'me@x.example',
+      fromName: 'Jürgen',
+      automatic: true,
+      subject: 'Gelesen: Grüße',
+    });
+    expect(raw).toContain('Disposition: automatic-action/MDN-sent-automatically; displayed');
+    expect(raw).toContain('From: =?UTF-8?B?');
+    expect(raw).toContain('Subject: =?UTF-8?B?');
+    expect(raw).not.toContain('In-Reply-To');
+  });
+});
+
+describe('helpers', () => {
+  it('leaves ASCII header words alone', () => {
+    expect(encodeHeaderWord('plain')).toBe('plain');
+  });
+  it('formats RFC 5322 dates in UTC', () => {
+    expect(rfc5322Date(new Date(Date.UTC(2026, 4, 28, 14, 23, 0)))).toBe('Thu, 28 May 2026 14:23:00 +0000');
+  });
+});
diff --git a/src/lib/__tests__/tnef.test.ts b/src/lib/__tests__/tnef.test.ts
new file mode 100644
index 00000000..f63b42df
--- /dev/null
+++ b/src/lib/__tests__/tnef.test.ts
@@ -0,0 +1,76 @@
+import { describe, it, expect } from 'vitest';
+import { parseTnef, isTnefAttachment } from '../tnef';
+
+function u32(n: number): number[] {
+  return [n & 0xff, (n >> 8) & 0xff, (n >> 16) & 0xff, (n >>> 24) & 0xff];
+}
+
+function attr(level: number, id: number, data: number[]): number[] {
+  return [level, ...u32(id), ...u32(data.length), ...data, 0, 0];
+}
+
+function bytes(s: string): number[] {
+  return Array.from(new TextEncoder().encode(s));
+}
+
+describe('parseTnef', () => {
+  it('rejects non-TNEF data', () => {
+    expect(parseTnef(new Uint8Array([1, 2, 3, 4, 5, 6, 7, 8]))).toEqual({ body: null, htmlBody: null, attachments: [] });
+    expect(parseTnef(new Uint8Array(2)).attachments).toEqual([]);
+  });
+
+  it('extracts the plain body and a simple attachment', () => {
+    const data = new Uint8Array([
+      ...u32(0x223e9f78), 0x00, 0x00,
+      ...attr(0x01, 0x0002800c, bytes('Hello body')),
+      ...attr(0x02, 0x00069002, [0, 0, 0, 0]),
+      ...attr(0x02, 0x00018010, [...bytes('file.txt'), 0]),
+      ...attr(0x02, 0x0006800f, bytes('payload')),
+    ]);
+    const res = parseTnef(data);
+    expect(res.body).toBe('Hello body');
+    expect(res.attachments).toHaveLength(1);
+    expect(res.attachments[0].name).toBe('file.txt');
+    expect(new TextDecoder().decode(res.attachments[0].data)).toBe('payload');
+    expect(res.attachments[0].mimeType).toBe('application/octet-stream');
+  });
+
+  it('reads the HTML body and long filename from MAPI props', () => {
+    // One PT_STRING8 property: type 0x001e, id 0x1013 (PR_BODY_HTML), count 1, value.
+    const html = [...bytes('<p>hi</p>'), 0];
+    const pad = (4 - (html.length % 4)) % 4;
+    const mapi = [
+      ...u32(1),
+      0x1e, 0x00, 0x13, 0x10,
+      ...u32(1),
+      ...u32(html.length), ...html, ...new Array(pad).fill(0),
+    ];
+    const name = [...bytes('report.pdf'), 0];
+    const npad = (4 - (name.length % 4)) % 4;
+    const mime = [...bytes('application/pdf'), 0];
+    const mpad = (4 - (mime.length % 4)) % 4;
+    const attMapi = [
+      ...u32(2),
+      0x1e, 0x00, 0x07, 0x37, ...u32(1), ...u32(name.length), ...name, ...new Array(npad).fill(0),
+      0x1e, 0x00, 0x0e, 0x37, ...u32(1), ...u32(mime.length), ...mime, ...new Array(mpad).fill(0),
+    ];
+    const data = new Uint8Array([
+      ...u32(0x223e9f78), 0x00, 0x00,
+      ...attr(0x01, 0x00069003, mapi),
+      ...attr(0x02, 0x00069002, [0]),
+      ...attr(0x02, 0x0006800f, bytes('%PDF')),
+      ...attr(0x02, 0x00069005, attMapi),
+    ]);
+    const res = parseTnef(data);
+    expect(res.htmlBody).toBe('<p>hi</p>');
+    expect(res.attachments[0]).toMatchObject({ name: 'report.pdf', mimeType: 'application/pdf' });
+  });
+});
+
+describe('isTnefAttachment', () => {
+  it('matches by name or type', () => {
+    expect(isTnefAttachment('WINMAIL.DAT', 'application/octet-stream')).toBe(true);
+    expect(isTnefAttachment('x.bin', 'application/ms-tnef')).toBe(true);
+    expect(isTnefAttachment('x.bin', 'application/pdf')).toBe(false);
+  });
+});
diff --git a/src/lib/attachment-display.ts b/src/lib/attachment-display.ts
new file mode 100644
index 00000000..f8486996
--- /dev/null
+++ b/src/lib/attachment-display.ts
@@ -0,0 +1,135 @@
+// Attachment-chip helpers for the reader: display names for unnamed parts,
+// the parts that are hidden from the chip list, and preview classification.
+// Ports of the webmail's `getAttachmentDisplayName`, the attachment filter
+// chain in `components/email/email-viewer.tsx` and `lib/file-preview.ts`.
+
+import type { Attachment, Email } from '../api/types';
+import { findCalendarAttachment } from './calendar-invitation';
+
+const MIME_TYPE_LABELS: Record<string, string> = {
+  'application/pdf': 'Document.pdf',
+  'application/zip': 'Archive.zip',
+  'application/x-zip-compressed': 'Archive.zip',
+  'application/gzip': 'Archive.gz',
+  'application/x-rar-compressed': 'Archive.rar',
+  'application/x-7z-compressed': 'Archive.7z',
+  'application/msword': 'Document.doc',
+  'application/vnd.openxmlformats-officedocument.wordprocessingml.document': 'Document.docx',
+  'application/vnd.ms-excel': 'Spreadsheet.xls',
+  'application/vnd.openxmlformats-officedocument.spreadsheetml.sheet': 'Spreadsheet.xlsx',
+  'application/vnd.ms-powerpoint': 'Presentation.ppt',
+  'application/vnd.openxmlformats-officedocument.presentationml.presentation': 'Presentation.pptx',
+  'text/plain': 'Text.txt',
+  'text/html': 'Document.html',
+  'text/csv': 'Data.csv',
+  'application/json': 'Data.json',
+  'application/xml': 'Data.xml',
+  'application/octet-stream': 'Attachment',
+  'message/rfc822': 'Email.eml',
+};
+
+export function getAttachmentDisplayName(name: string | null | undefined, mimeType?: string): string {
+  if (name) return name;
+  if (mimeType) {
+    const base = mimeType.split(';')[0].trim().toLowerCase();
+    const label = MIME_TYPE_LABELS[base];
+    if (label) return label;
+    const sub = base.split('/')[1];
+    if (sub) {
+      const clean = sub.replace(/^x-/, '').replace(/^vnd\./, '');
+      return `Attachment.${clean}`;
+    }
+  }
+  return 'Attachment';
+}
+
+const CAL_MIME = new Set(['text/calendar', 'application/ics', 'application/icalendar']);
+
+export function isCalendarMimeType(type?: string | null): boolean {
+  if (!type) return false;
+  return CAL_MIME.has(type.split(';')[0].trim().toLowerCase());
+}
+
+/** Machine-readable report parts (MDN receipts, DSN bounces) - never real attachments. */
+export function isReportPart(type?: string | null): boolean {
+  const base = (type || '').split(';')[0].trim().toLowerCase();
+  return base === 'message/disposition-notification' || base === 'message/delivery-status';
+}
+
+export function isRfc822Attachment(att: Pick<Attachment, 'name' | 'type'>): boolean {
+  const base = (att.type || '').split(';')[0].trim().toLowerCase();
+  return base === 'message/rfc822' || /\.eml$/i.test(att.name || '');
+}
+
+export function isTnefAttachment(name?: string | null, type?: string | null): boolean {
+  const lowerName = (name || '').toLowerCase();
+  const lowerType = (type || '').split(';')[0].trim().toLowerCase();
+  return (
+    lowerName === 'winmail.dat'
+    || lowerType === 'application/ms-tnef'
+    || lowerType === 'application/vnd.ms-tnef'
+  );
+}
+
+export interface VisibleAttachmentOptions {
+  hideInlineImageAttachments: boolean;
+  /** True when the calendar-invitation banner renders for this message. */
+  calendarBannerShown: boolean;
+  /** True when a TNEF container was unpacked (its inner files are listed instead). */
+  tnefUnpacked?: boolean;
+}
+
+/**
+ * The attachments that get a chip. Mirrors the webmail filter chain:
+ *  - inline cid images are hidden only when their disposition really is
+ *    `inline` (an image with a Content-ID but `disposition: attachment` is a
+ *    real attachment the body may never reference);
+ *  - calendar parts are hidden while the invitation banner shows them;
+ *  - MDN/DSN report parts are never listed;
+ *  - winmail.dat is hidden once its content was extracted.
+ */
+export function visibleAttachments(email: Pick<Email, 'attachments'>, opts: VisibleAttachmentOptions): Attachment[] {
+  const all = email.attachments ?? [];
+  return all.filter((att) => {
+    if (isReportPart(att.type)) return false;
+    if (opts.calendarBannerShown && isCalendarMimeType(att.type)) return false;
+    if (opts.tnefUnpacked && isTnefAttachment(att.name, att.type)) return false;
+    if (
+      opts.hideInlineImageAttachments
+      && att.cid
+      && att.disposition === 'inline'
+      && (att.type || '').toLowerCase().startsWith('image/')
+    ) return false;
+    return true;
+  });
+}
+
+/** Whether the calendar banner will render for this message. */
+export function calendarBannerShownFor(email: Pick<Email, 'attachments'>, parsingEnabled: boolean): boolean {
+  return parsingEnabled && !!findCalendarAttachment(email);
+}
+
+export type PreviewKind = 'image' | 'pdf' | 'text' | 'eml' | 'none';
+
+const TEXT_EXT = /\.(txt|md|markdown|csv|log|json|xml|ics|vcf|yml|yaml|ini|conf|diff|patch)$/i;
+// Script-bearing types are never previewed inline (html/svg/js) - webmail lib/file-preview.ts.
+const SCRIPT_TYPES = /^(text\/html|image\/svg\+xml|application\/(x-)?javascript|text\/javascript|application\/xhtml\+xml)$/i;
+
+/** How the in-app preview should render a part, if at all. */
+export function previewKindFor(att: Pick<Attachment, 'name' | 'type'>): PreviewKind {
+  const base = (att.type || '').split(';')[0].trim().toLowerCase();
+  const name = att.name || '';
+  if (SCRIPT_TYPES.test(base) || /\.(html?|svg|js)$/i.test(name)) return 'none';
+  if (isRfc822Attachment(att)) return 'eml';
+  if (base.startsWith('image/') || /\.(png|jpe?g|gif|webp|bmp|heic|avif)$/i.test(name)) return 'image';
+  if (base === 'application/pdf' || /\.pdf$/i.test(name)) return 'pdf';
+  if (base.startsWith('text/') || base === 'application/json' || base === 'application/xml' || TEXT_EXT.test(name)) return 'text';
+  return 'none';
+}
+
+export function formatSize(bytes?: number): string {
+  if (!bytes) return '';
+  if (bytes < 1024) return `${bytes} B`;
+  if (bytes < 1024 * 1024) return `${(bytes / 1024).toFixed(1)} KB`;
+  return `${(bytes / (1024 * 1024)).toFixed(1)} MB`;
+}
diff --git a/src/lib/email-date.ts b/src/lib/email-date.ts
new file mode 100644
index 00000000..90fb5aff
--- /dev/null
+++ b/src/lib/email-date.ts
@@ -0,0 +1,75 @@
+/**
+ * Which timestamp to show for a message. Port of the webmail's
+ * `lib/email-date.ts`.
+ *
+ * JMAP `receivedAt` is the server's internal date - the moment the message
+ * landed in the store. An import, migration or backup restore that does not
+ * preserve internal dates stamps every message with the import time, so a
+ * whole mailbox suddenly "arrived" today (#891). `sentAt` is the RFC 5322
+ * `Date` header, which survives such moves and is what Thunderbird, Outlook
+ * and Apple Mail display.
+ *
+ * Prefer `sentAt`; fall back to `receivedAt` when the header is missing,
+ * unparsable, or implausibly far in the future relative to the receive time
+ * (spam forges future dates to float to the top of date-sorted lists).
+ */
+
+import type { TimeFormat } from '../stores/settings-store';
+
+/** How far ahead of `receivedAt` a `Date` header may be before it is ignored. */
+export const MAX_FUTURE_SENT_AT_MS = 24 * 60 * 60 * 1000;
+
+interface DatedEmail {
+  sentAt?: string | null;
+  receivedAt?: string | null;
+}
+
+type DisplayDate<T extends DatedEmail> = T extends { receivedAt: string } ? string : string | undefined;
+
+export function emailDisplayDate<T extends DatedEmail>(email: T): DisplayDate<T> {
+  const { sentAt, receivedAt } = email;
+  const fallback = (receivedAt ?? undefined) as DisplayDate<T>;
+  if (!sentAt) return fallback;
+  const sent = Date.parse(sentAt);
+  if (Number.isNaN(sent)) return fallback;
+  if (receivedAt) {
+    const received = Date.parse(receivedAt);
+    if (!Number.isNaN(received) && sent - received > MAX_FUTURE_SENT_AT_MS) return fallback;
+  }
+  return sentAt as DisplayDate<T>;
+}
+
+function intlLocale(locale?: string): string {
+  return !locale || locale === 'en' ? 'en-US' : locale;
+}
+
+/** "Mon, 3 Jun 2026" in the app locale. */
+export function formatHeaderDate(iso: string | undefined, locale?: string): string {
+  if (!iso) return '';
+  const d = new Date(iso);
+  if (Number.isNaN(d.getTime())) return '';
+  return d.toLocaleDateString(intlLocale(locale), {
+    weekday: 'short', year: 'numeric', month: 'short', day: 'numeric',
+  });
+}
+
+/** "14:05" / "2:05 PM" honouring the app's time-format setting. */
+export function formatHeaderTime(iso: string | undefined, timeFormat: TimeFormat, locale?: string): string {
+  if (!iso) return '';
+  const d = new Date(iso);
+  if (Number.isNaN(d.getTime())) return '';
+  return d.toLocaleTimeString(intlLocale(locale), {
+    hour: '2-digit', minute: '2-digit', hour12: timeFormat === '12h',
+  });
+}
+
+/** Full date + time for the details panel. */
+export function formatFullDateTime(iso: string | undefined, timeFormat: TimeFormat, locale?: string): string {
+  if (!iso) return '';
+  const d = new Date(iso);
+  if (Number.isNaN(d.getTime())) return '';
+  return d.toLocaleString(intlLocale(locale), {
+    weekday: 'short', year: 'numeric', month: 'short', day: 'numeric',
+    hour: '2-digit', minute: '2-digit', hour12: timeFormat === '12h',
+  });
+}
diff --git a/src/lib/email-export.ts b/src/lib/email-export.ts
index 1c9eb492..d8b404ee 100644
--- a/src/lib/email-export.ts
+++ b/src/lib/email-export.ts
@@ -270,9 +270,30 @@ export async function downloadAttachment(
   });
 }
 
-/** Share an already-materialised local file (zip bundles, extracted parts). */
-export async function shareLocalFile(file: File, mimeType: string, dialogTitle?: string): Promise<void> {
-  if (Platform.OS === 'android' && (await openWithViewer(file, mimeType))) return;
+/** Write bytes into the exports cache (caller shares / previews / cleans up). */
+export function writeTempFile(bytes: Uint8Array, filename: string, mimeType?: string): File {
+  void sweepStaleExportFiles();
+  const dir = exportsDir();
+  ensureDir(dir);
+  const file = new File(dir, safeAttachmentName(filename, mimeType));
+  if (file.exists) file.delete();
+  file.create();
+  file.write(bytes);
+  return file;
+}
+
+/**
+ * Share an already-materialised local file (zip bundles, extracted parts).
+ * `forceSheet` skips the Android viewer handoff and always shows the share
+ * sheet - the explicit "Share" action, as opposed to "Open".
+ */
+export async function shareLocalFile(
+  file: File,
+  mimeType: string,
+  dialogTitle?: string,
+  opts: { forceSheet?: boolean } = {},
+): Promise<void> {
+  if (!opts.forceSheet && Platform.OS === 'android' && (await openWithViewer(file, mimeType))) return;
   if (!(await Sharing.isAvailableAsync())) {
     throw new Error('Sharing is not available on this device');
   }
@@ -284,15 +305,30 @@ export async function shareLocalFile(file: File, mimeType: string, dialogTitle?:
 }
 
 /** Write bytes to the exports cache and hand them to a viewer / the share sheet. */
-export async function shareBytes(bytes: Uint8Array, filename: string, mimeType: string): Promise<void> {
-  void sweepStaleExportFiles();
-  const dir = exportsDir();
-  ensureDir(dir);
-  const file = new File(dir, safeAttachmentName(filename, mimeType));
-  if (file.exists) file.delete();
-  file.create();
-  file.write(bytes);
-  await shareLocalFile(file, mimeType, filename);
+export async function shareBytes(
+  bytes: Uint8Array,
+  filename: string,
+  mimeType: string,
+  opts: { forceSheet?: boolean } = {},
+): Promise<void> {
+  const file = writeTempFile(bytes, filename, mimeType);
+  await shareLocalFile(file, mimeType, filename, opts);
+}
+
+/** Share a blob through the share sheet only (no viewer handoff). */
+export async function shareAttachmentViaSheet(
+  blobId: string,
+  name: string | undefined,
+  type: string | undefined,
+  email?: Email | null,
+  accountId?: string,
+): Promise<void> {
+  const filename = email
+    ? attachmentDownloadFilename(email, { name, type }, attachmentFileOptions())
+    : safeAttachmentName(name, type);
+  const mimeType = type || 'application/octet-stream';
+  const downloaded = await cacheBlobFile(blobId, filename, mimeType, accountId);
+  await shareLocalFile(downloaded, mimeType, filename, { forceSheet: true });
 }
 
 async function authedBlobFetch(url: string): Promise<Response> {
@@ -323,7 +359,7 @@ export async function fetchBlobBytes(
   return new Uint8Array(await r.arrayBuffer());
 }
 
-function bytesToBase64(bytes: Uint8Array): string {
+export function bytesToBase64(bytes: Uint8Array): string {
   let binary = '';
   const chunk = 0x8000;
   for (let i = 0; i < bytes.length; i += chunk) {
diff --git a/src/lib/email-headers.ts b/src/lib/email-headers.ts
new file mode 100644
index 00000000..3b61f202
--- /dev/null
+++ b/src/lib/email-headers.ts
@@ -0,0 +1,310 @@
+// Header-derived metadata for the reader: SPF/DKIM/DMARC results, spam
+// scores, mailing-list headers and read-receipt requests. Port of the
+// webmail's `lib/email-headers.ts` plus the header lookups the viewer did
+// inline; RN gets raw `headers` (RFC 8621 §4.1.3, an array of {name, value})
+// from Email/get instead of the webmail's pre-parsed fields.
+
+import type { Email, Identity } from '../api/types';
+import { parseUnsubscribeUrls, type UnsubscribeUrls } from './unsubscribe';
+import { resolveReplyFrom } from './reply-identity';
+
+/**
+ * The identity a received message was addressed to (exact or `+tag`), for
+ * the "via <identity>" badge and as the MDN sender. Falls back to the first
+ * identity.
+ */
+export function findReceivingIdentity(
+  identities: Identity[],
+  email: Pick<Email, 'to' | 'cc' | 'bcc'>,
+): Identity | undefined {
+  if (identities.length === 0) return undefined;
+  const resolved = resolveReplyFrom(identities, {
+    to: email.to ?? undefined, cc: email.cc ?? undefined, bcc: email.bcc ?? undefined,
+  });
+  if (resolved && !resolved.overrideEmail) {
+    return identities.find((i) => i.id === resolved.identityId) ?? identities[0];
+  }
+  return identities[0];
+}
+
+export type SpfResult = 'pass' | 'fail' | 'softfail' | 'neutral' | 'none' | 'temperror' | 'permerror';
+export type DkimResult = 'pass' | 'fail' | 'policy' | 'neutral' | 'temperror' | 'permerror';
+export type DmarcResult = 'pass' | 'fail' | 'none';
+export type DmarcPolicy = 'reject' | 'quarantine' | 'none';
+
+export interface SpfEntry {
+  result: SpfResult;
+  identity?: 'mailfrom' | 'helo';
+  domain?: string;
+}
+
+export interface AuthenticationResults {
+  spf?: { result: SpfResult; domain?: string; all?: SpfEntry[] };
+  dkim?: { result: DkimResult; domain?: string; selector?: string };
+  dmarc?: { result: DmarcResult; domain?: string; policy?: DmarcPolicy };
+  iprev?: { result: 'pass' | 'fail'; ip?: string };
+}
+
+type HeaderList = Email['headers'];
+
+/** All values of a header, case-insensitively, in message order. */
+export function headerValues(headers: HeaderList, name: string): string[] {
+  if (!headers) return [];
+  const needle = name.toLowerCase();
+  return headers.filter((h) => h.name.toLowerCase() === needle).map((h) => h.value.trim());
+}
+
+/** First value of a header, case-insensitively. */
+export function headerValue(headers: HeaderList, name: string): string | undefined {
+  return headerValues(headers, name)[0];
+}
+
+/** Collapse the header array to a name → value(s) record (first-seen casing). */
+export function headersToRecord(headers: HeaderList): Record<string, string | string[]> {
+  const out: Record<string, string | string[]> = {};
+  const canonical = new Map<string, string>();
+  for (const h of headers ?? []) {
+    const key = canonical.get(h.name.toLowerCase()) ?? h.name;
+    canonical.set(h.name.toLowerCase(), key);
+    const value = h.value.trim();
+    const existing = out[key];
+    if (existing === undefined) out[key] = value;
+    else if (Array.isArray(existing)) existing.push(value);
+    else out[key] = [existing, value];
+  }
+  return out;
+}
+
+/**
+ * Severity ranking for SPF results. Higher = more severe / more actionable.
+ * A hard `fail` is a definitive policy violation and must outrank ambiguous
+ * states like `temperror`.
+ */
+const SPF_SEVERITY: Record<SpfResult, number> = {
+  fail: 6,
+  softfail: 5,
+  permerror: 4,
+  temperror: 3,
+  neutral: 2,
+  none: 1,
+  pass: 0,
+};
+
+/**
+ * Whether the authentication results indicate the visible From identity can't
+ * be trusted (i.e. the message is likely spoofed). Used to suppress UI that
+ * would otherwise imply the message legitimately came from one of the user's
+ * own identities (e.g. the "via <identity>" badge).
+ */
+export function isAuthenticationSpoofed(auth?: AuthenticationResults): boolean {
+  if (!auth) return false;
+  if (auth.dmarc?.result === 'fail') return true;
+  if (auth.spf?.result === 'fail' && auth.dkim?.result !== 'pass') return true;
+  return false;
+}
+
+/** Parse an Authentication-Results header into SPF, DKIM, DMARC, iprev results. */
+export function parseAuthenticationResults(header: string): AuthenticationResults {
+  const results: AuthenticationResults = {};
+
+  // A single header can carry more than one SPF result when the server
+  // evaluates multiple identities (HELO and MAIL FROM). Collect them all so a
+  // hard fail on any identity isn't softened to an ambiguous state recorded
+  // for another one.
+  const spfRegex = /spf=(\w+)(?:\s+\([^)]*\))?(?:\s+smtp\.(mailfrom|helo)=([^\s;]+))?/g;
+  const spfResults: SpfEntry[] = [];
+  let spfM: RegExpExecArray | null;
+  while ((spfM = spfRegex.exec(header)) !== null) {
+    spfResults.push({
+      result: spfM[1] as SpfResult,
+      identity: spfM[2] as SpfEntry['identity'],
+      domain: spfM[3],
+    });
+  }
+  if (spfResults.length > 0) {
+    const severity = (r: string) => SPF_SEVERITY[r as SpfResult] ?? -1;
+    // MAIL FROM is the primary SPF identity. Another identity (HELO) may only
+    // escalate the headline to a genuine failure state - a HELO `none` or
+    // `neutral` must not downgrade a MAIL FROM `pass`.
+    const isFailure = (r: string) => severity(r) >= SPF_SEVERITY.temperror;
+    let primary = spfResults.find((e) => e.identity === 'mailfrom') ?? spfResults[0];
+    for (const cur of spfResults) {
+      if (isFailure(cur.result) && severity(cur.result) > severity(primary.result)) {
+        primary = cur;
+      }
+    }
+    results.spf = {
+      result: primary.result,
+      domain: primary.domain,
+      ...(spfResults.length > 1 ? { all: spfResults } : {}),
+    };
+  }
+
+  const dkimMatch = header.match(/dkim=(\w+)(?:\s+header\.d=([^\s;]+))?(?:\s+header\.s=([^\s;]+))?/);
+  if (dkimMatch) {
+    results.dkim = {
+      result: dkimMatch[1] as DkimResult,
+      domain: dkimMatch[2],
+      selector: dkimMatch[3],
+    };
+  }
+
+  const dmarcMatch = header.match(/dmarc=(\w+)(?:\s+header\.from=([^\s;]+))?(?:\s+policy\.dmarc=(\w+))?/);
+  if (dmarcMatch) {
+    results.dmarc = {
+      result: dmarcMatch[1] as DmarcResult,
+      domain: dmarcMatch[2],
+      policy: dmarcMatch[3] as DmarcPolicy | undefined,
+    };
+  }
+
+  const iprevMatch = header.match(/iprev=(\w+)(?:\s+policy\.iprev=([\d.]+))?/);
+  if (iprevMatch) {
+    results.iprev = {
+      result: iprevMatch[1] as 'pass' | 'fail',
+      ip: iprevMatch[2],
+    };
+  }
+
+  return results;
+}
+
+/** Parse a spam score from X-Spam-Result / X-Spam-Status / X-Spam-Score. */
+export function parseSpamScore(header: string): { score: number; status: string } | null {
+  // X-Spam-Status: "No, score=-0.25" / Stalwart X-Spam-Result: "ham, score=-0.25"
+  const statusMatch = header.match(/^(Yes|No|spam|ham),?\s+score=([-\d.]+)/i);
+  if (statusMatch) {
+    return {
+      status: statusMatch[1].toLowerCase(),
+      score: parseFloat(statusMatch[2]),
+    };
+  }
+
+  const scoreMatch = header.match(/score[=:]?\s*([-\d.]+)/i);
+  if (scoreMatch) {
+    const score = parseFloat(scoreMatch[1]);
+    return {
+      score,
+      status: score > 5 ? 'spam' : 'ham',
+    };
+  }
+
+  return null;
+}
+
+/** Parse the X-Spam-LLM header: "LEGITIMATE (explanation)" / "SPAM (...)". */
+export function parseSpamLLM(header: string): { verdict: string; explanation: string } | null {
+  const trimmed = header.trim();
+  const match = trimmed.match(/^(LEGITIMATE|SPAM|SUSPICIOUS)\s*\((.+)\)\s*$/i);
+  if (match) {
+    return {
+      verdict: match[1].toUpperCase(),
+      explanation: match[2].trim(),
+    };
+  }
+  return null;
+}
+
+export interface ListHeaders {
+  listId?: string;
+  listUnsubscribe?: UnsubscribeUrls;
+  /** RFC 8058: present when the http URL accepts a one-click POST. */
+  listUnsubscribePost?: string;
+  listHelp?: string;
+  listPost?: string;
+}
+
+/** Extract list headers (List-Unsubscribe, List-Id, ...). */
+export function extractListHeaders(headers: Record<string, string | string[]>): ListHeaders {
+  const result: ListHeaders = {};
+  const first = (key: string): string | undefined => {
+    const found = Object.keys(headers).find((k) => k.toLowerCase() === key.toLowerCase());
+    if (!found) return undefined;
+    const v = headers[found];
+    return Array.isArray(v) ? v[0] : v;
+  };
+
+  const listId = first('List-Id');
+  if (listId) result.listId = listId;
+
+  const unsub = first('List-Unsubscribe');
+  if (unsub) {
+    const parsed = parseUnsubscribeUrls(unsub);
+    if (parsed.preferred) result.listUnsubscribe = parsed;
+  }
+
+  const post = first('List-Unsubscribe-Post');
+  if (post) result.listUnsubscribePost = post;
+
+  const help = first('List-Help');
+  if (help) result.listHelp = help;
+
+  const listPost = first('List-Post');
+  if (listPost) result.listPost = listPost;
+
+  return result;
+}
+
+export interface EmailHeaderInfo {
+  auth?: AuthenticationResults;
+  spamScore?: { score: number; status: string } | null;
+  spamLLM?: { verdict: string; explanation: string } | null;
+  list: ListHeaders;
+  /** Bare address from Disposition-Notification-To, when a receipt was requested. */
+  readReceiptRequestedBy: string | null;
+  /** `<...>`-stripped Message-ID header, for dedupe keys. */
+  messageId: string | null;
+}
+
+/** Everything the reader derives from a message's raw headers, in one pass. */
+export function deriveHeaderInfo(email: Pick<Email, 'headers' | 'messageId'>): EmailHeaderInfo {
+  const headers = email.headers;
+  const authHeaders = headerValues(headers, 'Authentication-Results');
+  // The last hop's results are prepended, so the first header is the
+  // receiving server's own verdict.
+  const auth = authHeaders.length ? parseAuthenticationResults(authHeaders.join('; ')) : undefined;
+
+  const spamRaw = headerValue(headers, 'X-Spam-Status')
+    ?? headerValue(headers, 'X-Spam-Result')
+    ?? headerValue(headers, 'X-Spam-Score');
+  const spamScore = spamRaw ? parseSpamScore(spamRaw) : null;
+  const llmRaw = headerValue(headers, 'X-Spam-LLM');
+  const spamLLM = llmRaw ? parseSpamLLM(llmRaw) : null;
+
+  const list = extractListHeaders(headersToRecord(headers));
+
+  const dnt = headerValue(headers, 'Disposition-Notification-To');
+  let readReceiptRequestedBy: string | null = null;
+  if (dnt) {
+    const m = dnt.match(/<([^>]+)>/);
+    const addr = (m ? m[1] : dnt).trim();
+    readReceiptRequestedBy = addr || null;
+  }
+
+  const rawId = email.messageId?.[0] ?? headerValue(headers, 'Message-ID') ?? null;
+  const messageId = rawId ? rawId.trim().replace(/^<|>$/g, '') : null;
+
+  return { auth, spamScore, spamLLM, list, readReceiptRequestedBy, messageId };
+}
+
+/** Milliseconds between the Date header and delivery, or null when unknown. */
+export function deliveryDeltaMs(email: Pick<Email, 'sentAt' | 'receivedAt'>): number | null {
+  if (!email.sentAt || !email.receivedAt) return null;
+  const sent = Date.parse(email.sentAt);
+  const received = Date.parse(email.receivedAt);
+  if (Number.isNaN(sent) || Number.isNaN(received)) return null;
+  return received - sent;
+}
+
+/** "2 h 5 min" style rendering of a positive delta. */
+export function formatDelta(ms: number): string {
+  const totalMinutes = Math.round(Math.abs(ms) / 60000);
+  const days = Math.floor(totalMinutes / 1440);
+  const hours = Math.floor((totalMinutes % 1440) / 60);
+  const minutes = totalMinutes % 60;
+  const parts: string[] = [];
+  if (days) parts.push(`${days} d`);
+  if (hours) parts.push(`${hours} h`);
+  if (minutes || parts.length === 0) parts.push(`${minutes} min`);
+  return parts.join(' ');
+}
diff --git a/src/lib/forward-as-attachment.ts b/src/lib/forward-as-attachment.ts
new file mode 100644
index 00000000..b461b1a8
--- /dev/null
+++ b/src/lib/forward-as-attachment.ts
@@ -0,0 +1,45 @@
+import type { Attachment, Email } from '../api/types';
+import { buildForwardSubject } from './subject-prefix';
+import { emailExportFilename, type EmailFilenameOptions } from './download-filename';
+
+export interface ForwardAsAttachmentPayload {
+  subject: string;
+  attachment: Attachment & { type: 'message/rfc822' };
+}
+
+/**
+ * Build the subject and synthetic attachment entry for forwarding a message
+ * as a message/rfc822 attachment instead of inline-quoted text (e.g.
+ * reporting spam to a gateway that expects the raw original, or preserving
+ * exact formatting/headers). Port of the webmail's `lib/forward-as-attachment.ts`.
+ *
+ * Referenced by blobId, not re-uploaded - JMAP blobs are account-scoped, so
+ * the blobId a message already has can be attached to a new outgoing email
+ * directly (the composer re-uploads when the owner is a shared account).
+ *
+ * `filenameOptions` carries the user's space/case/diacritics transforms; its
+ * `template` is ignored: the attachment goes out to a possibly external
+ * recipient, so the filename is always "{date}-{subject}.eml" - never the
+ * user's own from/to naming template, which could leak names.
+ *
+ * Returns null when the email has no blobId.
+ */
+export function buildForwardAsAttachmentPayload(
+  email: Email,
+  forwardPrefix: string,
+  filenameOptions?: EmailFilenameOptions,
+): ForwardAsAttachmentPayload | null {
+  if (!email.blobId) return null;
+
+  return {
+    // Match the normal Forward flow, which leaves the subject blank rather
+    // than prefix-only when the original has none.
+    subject: email.subject ? buildForwardSubject(email.subject, forwardPrefix) : '',
+    attachment: {
+      blobId: email.blobId,
+      name: emailExportFilename(email, { ...filenameOptions, template: '{date}-{subject}' }),
+      type: 'message/rfc822',
+      size: email.size,
+    },
+  };
+}
diff --git a/src/lib/mdn.ts b/src/lib/mdn.ts
new file mode 100644
index 00000000..5a08f23b
--- /dev/null
+++ b/src/lib/mdn.ts
@@ -0,0 +1,163 @@
+// Builds an RFC 8098 Message Disposition Notification (MDN) as a raw RFC 5322
+// message string. JMAP/Stalwart has no native MDN support, so the client
+// constructs the multipart/report itself and sends it via
+// blob-upload -> Email/import -> EmailSubmission/set (see api/email sendMdn).
+// Port of the webmail's `lib/mdn.ts`.
+//
+// The message has two parts:
+//   1. text/plain  - human-readable explanation (rarely shown)
+//   2. message/disposition-notification - the machine-readable fields
+// The optional third part (original message/headers) is omitted; RFC 8098 §3.1
+// permits a two-part report.
+
+export interface MdnOptions {
+  /** Address that requested the receipt (Disposition-Notification-To) - the MDN recipient. */
+  to: string;
+  /** Our identity address (sender of the MDN). */
+  fromEmail: string;
+  /** Optional display name for the From header. */
+  fromName?: string;
+  /** Original Message-ID. JMAP may hand this back as a string[]. */
+  originalMessageId?: string | string[] | null;
+  /** Original Subject (used to build the MDN subject). */
+  originalSubject?: string;
+  /**
+   * The address the original message was delivered to (our address/alias).
+   * Used for Final-Recipient/Original-Recipient. Falls back to fromEmail.
+   */
+  originalRecipient?: string;
+  /** true => automatic-action (setting "always"); false => manual-action (user tapped send). */
+  automatic?: boolean;
+  /** Reporting-UA value, e.g. "mail.example; Bulwark Mobile". */
+  reportingUa?: string;
+  /** Localized full Subject line. Defaults to "Read: <originalSubject>". */
+  subject?: string;
+  /** Localized human-readable explanation (first report part). Defaults to English. */
+  humanText?: string;
+}
+
+const DAYS = ['Sun', 'Mon', 'Tue', 'Wed', 'Thu', 'Fri', 'Sat'];
+const MONTHS = ['Jan', 'Feb', 'Mar', 'Apr', 'May', 'Jun', 'Jul', 'Aug', 'Sep', 'Oct', 'Nov', 'Dec'];
+
+/** RFC 5322 date in UTC, e.g. "Thu, 28 May 2026 14:23:00 +0000". */
+export function rfc5322Date(d: Date = new Date()): string {
+  const pad = (n: number) => String(n).padStart(2, '0');
+  return `${DAYS[d.getUTCDay()]}, ${pad(d.getUTCDate())} ${MONTHS[d.getUTCMonth()]} ${d.getUTCFullYear()} `
+    + `${pad(d.getUTCHours())}:${pad(d.getUTCMinutes())}:${pad(d.getUTCSeconds())} +0000`;
+}
+
+function utf8Bytes(value: string): Uint8Array {
+  if (typeof TextEncoder !== 'undefined') return new TextEncoder().encode(value);
+  // Hermes ships TextEncoder; this is a defensive fallback for test runtimes.
+  const out: number[] = [];
+  for (const ch of value) {
+    const cp = ch.codePointAt(0)!;
+    if (cp < 0x80) out.push(cp);
+    else if (cp < 0x800) out.push(0xc0 | (cp >> 6), 0x80 | (cp & 0x3f));
+    else if (cp < 0x10000) out.push(0xe0 | (cp >> 12), 0x80 | ((cp >> 6) & 0x3f), 0x80 | (cp & 0x3f));
+    else out.push(0xf0 | (cp >> 18), 0x80 | ((cp >> 12) & 0x3f), 0x80 | ((cp >> 6) & 0x3f), 0x80 | (cp & 0x3f));
+  }
+  return new Uint8Array(out);
+}
+
+/** UTF-8 string -> base64. */
+export function utf8ToBase64(value: string): string {
+  const bytes = utf8Bytes(value);
+  let binary = '';
+  for (let i = 0; i < bytes.length; i++) binary += String.fromCharCode(bytes[i]);
+  return btoa(binary);
+}
+
+/** UTF-8 base64 body, wrapped at 76 chars per RFC 2045. */
+function base64Body(text: string): string {
+  return (utf8ToBase64(text).match(/.{1,76}/g) || []).join('\r\n');
+}
+
+/** RFC 2047 encoded-word for header values that contain non-ASCII characters. */
+export function encodeHeaderWord(value: string): string {
+  // eslint-disable-next-line no-control-regex
+  if (!/[^\x00-\x7F]/.test(value)) return value;
+  return `=?UTF-8?B?${utf8ToBase64(value)}?=`;
+}
+
+function ensureAngles(messageId: string | string[] | null | undefined): string {
+  const raw = Array.isArray(messageId) ? messageId[0] : messageId;
+  if (typeof raw !== 'string') return '';
+  const trimmed = raw.trim();
+  if (!trimmed) return '';
+  return trimmed.startsWith('<') ? trimmed : `<${trimmed}>`;
+}
+
+function randomToken(): string {
+  const rnd = Math.random().toString(36).slice(2);
+  return `${Date.now().toString(36)}.${rnd}`;
+}
+
+/**
+ * Build the raw RFC 5322 MDN message. Lines are CRLF-terminated as required
+ * by the MIME standard so the bytes import/transmit verbatim.
+ */
+export function buildMdnMessage(opts: MdnOptions): string {
+  const finalRecipient = opts.originalRecipient || opts.fromEmail;
+  const domain = (opts.fromEmail.split('@')[1] || 'localhost').trim();
+  const messageId = `<mdn.${randomToken()}@${domain}>`;
+  const boundary = `----=_MDN_${randomToken()}`;
+  const origMsgId = ensureAngles(opts.originalMessageId);
+
+  const fromHeader = opts.fromName
+    ? `${encodeHeaderWord(opts.fromName)} <${opts.fromEmail}>`
+    : opts.fromEmail;
+
+  const subject = encodeHeaderWord(
+    opts.subject ?? `Read: ${opts.originalSubject || ''}`.trim(),
+  );
+
+  const disposition = opts.automatic
+    ? 'automatic-action/MDN-sent-automatically; displayed'
+    : 'manual-action/MDN-sent-manually; displayed';
+
+  const reportingUa = opts.reportingUa || `${domain}; Bulwark Mobile`;
+
+  const humanText = opts.humanText ?? [
+    `This is a return receipt for the message you sent to ${finalRecipient}.`,
+    '',
+    'Note: This receipt only acknowledges that the message was displayed on the',
+    "recipient's device. There is no guarantee that the recipient has read or",
+    'understood the message contents.',
+  ].join('\r\n');
+
+  const mdnFields = [
+    `Reporting-UA: ${reportingUa}`,
+    `Final-Recipient: rfc822;${finalRecipient}`,
+    ...(opts.originalRecipient ? [`Original-Recipient: rfc822;${opts.originalRecipient}`] : []),
+    ...(origMsgId ? [`Original-Message-ID: ${origMsgId}`] : []),
+    `Disposition: ${disposition}`,
+  ].join('\r\n');
+
+  return [
+    `Date: ${rfc5322Date()}`,
+    `From: ${fromHeader}`,
+    `To: ${opts.to}`,
+    `Subject: ${subject}`,
+    `Message-ID: ${messageId}`,
+    ...(origMsgId ? [`In-Reply-To: ${origMsgId}`] : []),
+    'MIME-Version: 1.0',
+    'Content-Type: multipart/report; report-type=disposition-notification;',
+    `\tboundary="${boundary}"`,
+    '',
+    `--${boundary}`,
+    'Content-Type: text/plain; charset=utf-8',
+    'Content-Transfer-Encoding: base64',
+    '',
+    base64Body(humanText),
+    '',
+    `--${boundary}`,
+    'Content-Type: message/disposition-notification',
+    'Content-Transfer-Encoding: 7bit',
+    '',
+    mdnFields,
+    '',
+    `--${boundary}--`,
+    '',
+  ].join('\r\n');
+}
diff --git a/src/lib/smime.ts b/src/lib/smime.ts
new file mode 100644
index 00000000..1044d447
--- /dev/null
+++ b/src/lib/smime.ts
@@ -0,0 +1,23 @@
+import type { BodyPart, Email } from '../api/types';
+
+/**
+ * True when the message is S/MIME signed or encrypted (pkcs7 parts). Port of
+ * the webmail client's `isSmimeEmail`. The mobile app has no crypto path, so
+ * the reader only shows a "not supported" note for these.
+ */
+export function isSmimeEmail(email: Pick<Email, 'bodyStructure' | 'attachments'>): boolean {
+  const types: string[] = [];
+  const collect = (part: (BodyPart & { subParts?: BodyPart[] }) | undefined): void => {
+    if (!part) return;
+    if (part.type) types.push(part.type.toLowerCase());
+    part.subParts?.forEach(collect);
+  };
+  collect(email.bodyStructure as (BodyPart & { subParts?: BodyPart[] }) | undefined);
+  email.attachments?.forEach((att) => types.push((att.type || '').toLowerCase()));
+  return types.some((type) =>
+    type.includes('pkcs7')
+    || type.includes('x-pkcs7')
+    || type === 'application/pkcs7-mime'
+    || type === 'application/pkcs7-signature',
+  );
+}
diff --git a/src/lib/tnef.ts b/src/lib/tnef.ts
new file mode 100644
index 00000000..84a436b4
--- /dev/null
+++ b/src/lib/tnef.ts
@@ -0,0 +1,318 @@
+/**
+ * Minimal TNEF (Transport Neutral Encapsulation Format) parser. Port of the
+ * webmail's `lib/tnef.ts` without the debug logging.
+ *
+ * Parses winmail.dat files sent by Microsoft Outlook to extract the HTML
+ * body, plain text body, and embedded attachments.
+ *
+ * Reference: MS-OXTNEF / MS-TNEF specification.
+ */
+
+const TNEF_SIGNATURE = 0x223e9f78;
+
+const LVL_MESSAGE = 0x01;
+const LVL_ATTACHMENT = 0x02;
+
+// Message-level attribute IDs
+const attBody = 0x0002800c;
+const attMAPIProps = 0x00069003;
+
+// Attachment-level attribute IDs
+const attAttachRenddata = 0x00069002;
+const attAttachData = 0x0006800f;
+const attAttachTitle = 0x00018010;
+const attAttachment = 0x00069005;
+
+// MAPI property types
+const PT_SHORT = 0x0002;
+const PT_LONG = 0x0003;
+const PT_BOOLEAN = 0x000b;
+const PT_STRING8 = 0x001e;
+const PT_UNICODE = 0x001f;
+const PT_BINARY = 0x0102;
+const PT_SYSTIME = 0x0040;
+const PT_CLSID = 0x0048;
+const PT_I8 = 0x0014;
+
+const MV_FLAG = 0x1000;
+
+// MAPI property IDs
+const PR_BODY = 0x1000;
+const PR_BODY_HTML = 0x1013;
+const PR_ATTACH_LONG_FILENAME = 0x3707;
+const PR_ATTACH_MIME_TAG = 0x370e;
+const PR_ATTACH_DATA_BIN = 0x3701;
+
+export interface TnefAttachment {
+  name: string;
+  mimeType: string;
+  data: Uint8Array;
+}
+
+export interface TnefResult {
+  body: string | null;
+  htmlBody: string | null;
+  attachments: TnefAttachment[];
+}
+
+class BinaryReader {
+  private view: DataView;
+  private offset: number;
+  private bytes: Uint8Array;
+
+  constructor(data: Uint8Array) {
+    this.bytes = data;
+    this.view = new DataView(data.buffer, data.byteOffset, data.byteLength);
+    this.offset = 0;
+  }
+
+  readUint8(): number {
+    const val = this.view.getUint8(this.offset);
+    this.offset += 1;
+    return val;
+  }
+
+  readUint16LE(): number {
+    const val = this.view.getUint16(this.offset, true);
+    this.offset += 2;
+    return val;
+  }
+
+  readUint32LE(): number {
+    const val = this.view.getUint32(this.offset, true);
+    this.offset += 4;
+    return val;
+  }
+
+  readBytes(length: number): Uint8Array {
+    const slice = this.bytes.slice(this.offset, this.offset + length);
+    this.offset += length;
+    return slice;
+  }
+
+  skip(n: number): void {
+    this.offset += n;
+  }
+
+  get remaining(): number {
+    return this.bytes.byteLength - this.offset;
+  }
+}
+
+function pad4(len: number): number {
+  return (4 - (len % 4)) % 4;
+}
+
+function decodeUtf8(bytes: Uint8Array): string {
+  return new TextDecoder('utf-8').decode(bytes);
+}
+
+function decodeUtf16le(bytes: Uint8Array): string {
+  try {
+    return new TextDecoder('utf-16le').decode(bytes);
+  } catch {
+    // Hermes' TextDecoder only guarantees utf-8; decode by hand.
+    let out = '';
+    for (let i = 0; i + 1 < bytes.length; i += 2) {
+      out += String.fromCharCode(bytes[i] | (bytes[i + 1] << 8));
+    }
+    return out;
+  }
+}
+
+function readMAPIFixedValue(r: BinaryReader, propType: number): Uint8Array | number | null {
+  switch (propType) {
+    case PT_SHORT: {
+      const val = r.readUint16LE();
+      r.skip(2);
+      return val;
+    }
+    case PT_LONG:
+    case PT_BOOLEAN:
+      return r.readUint32LE();
+    case PT_I8:
+    case PT_SYSTIME:
+      return r.readBytes(8);
+    case PT_CLSID:
+      return r.readBytes(16);
+    default:
+      if (r.remaining >= 4) return r.readBytes(4);
+      return null;
+  }
+}
+
+function readMAPIVarValue(r: BinaryReader): Uint8Array | null {
+  if (r.remaining < 4) return null;
+  const length = r.readUint32LE();
+  if (length > r.remaining) return null;
+  const data = r.readBytes(length);
+  r.skip(pad4(length));
+  return data;
+}
+
+function isVarLengthType(baseType: number): boolean {
+  return baseType === PT_STRING8 || baseType === PT_UNICODE || baseType === PT_BINARY;
+}
+
+function decodeMAPIString(data: Uint8Array, propType: number): string {
+  if (propType === PT_UNICODE) {
+    let len = data.byteLength;
+    if (len >= 2 && data[len - 1] === 0 && data[len - 2] === 0) len -= 2;
+    return decodeUtf16le(data.subarray(0, len));
+  }
+  let len = data.byteLength;
+  if (len >= 1 && data[len - 1] === 0) len -= 1;
+  return decodeUtf8(data.subarray(0, len));
+}
+
+function parseMAPIProps(data: Uint8Array): Map<number, { type: number; value: Uint8Array | number | null }> {
+  const props = new Map<number, { type: number; value: Uint8Array | number | null }>();
+  const r = new BinaryReader(data);
+
+  if (r.remaining < 4) return props;
+  const count = r.readUint32LE();
+
+  for (let i = 0; i < count && r.remaining >= 4; i++) {
+    const propType = r.readUint16LE();
+    const propID = r.readUint16LE();
+
+    // Named properties (ID >= 0x8000) carry extra GUID + name data
+    if (propID >= 0x8000) {
+      if (r.remaining < 20) break;
+      r.skip(16);
+      const kind = r.readUint32LE();
+      if (kind === 0) {
+        if (r.remaining < 4) break;
+        r.skip(4);
+      } else {
+        if (r.remaining < 4) break;
+        const nameLen = r.readUint32LE();
+        if (nameLen > r.remaining) break;
+        r.skip(nameLen);
+        r.skip(pad4(nameLen));
+      }
+    }
+
+    const baseType = propType & 0x0fff;
+    const isMultiValue = (propType & MV_FLAG) !== 0;
+
+    if (isVarLengthType(baseType)) {
+      if (r.remaining < 4) break;
+      const valueCount = r.readUint32LE();
+      let lastValue: Uint8Array | null = null;
+      for (let j = 0; j < valueCount && r.remaining > 0; j++) {
+        lastValue = readMAPIVarValue(r);
+      }
+      if (!isMultiValue && lastValue) {
+        props.set(propID, { type: propType, value: lastValue });
+      }
+    } else if (isMultiValue) {
+      if (r.remaining < 4) break;
+      const valueCount = r.readUint32LE();
+      for (let j = 0; j < valueCount && r.remaining > 0; j++) {
+        readMAPIFixedValue(r, baseType);
+      }
+    } else {
+      const value = readMAPIFixedValue(r, baseType);
+      props.set(propID, { type: propType, value });
+    }
+  }
+
+  return props;
+}
+
+/** Parse a TNEF (winmail.dat) file and extract the body and attachments. */
+export function parseTnef(data: Uint8Array): TnefResult {
+  const result: TnefResult = { body: null, htmlBody: null, attachments: [] };
+
+  if (data.byteLength < 6) return result;
+
+  const r = new BinaryReader(data);
+  const signature = r.readUint32LE();
+  if (signature !== TNEF_SIGNATURE) return result;
+
+  r.skip(2); // legacy key
+
+  let curAttach: { name: string; mimeType: string; data: Uint8Array | null } | null = null;
+
+  while (r.remaining >= 11) {
+    const level = r.readUint8();
+    const attrID = r.readUint32LE();
+    const attrLen = r.readUint32LE();
+
+    if (attrLen > r.remaining - 2) break;
+
+    const attrData = r.readBytes(attrLen);
+    r.skip(2); // checksum
+
+    if (level === LVL_MESSAGE) {
+      if (attrID === attBody) {
+        result.body = decodeUtf8(attrData);
+      } else if (attrID === attMAPIProps) {
+        const props = parseMAPIProps(attrData);
+
+        const htmlProp = props.get(PR_BODY_HTML);
+        if (htmlProp?.value instanceof Uint8Array) {
+          const baseType = htmlProp.type & 0x0fff;
+          result.htmlBody = baseType === PT_STRING8 || baseType === PT_UNICODE
+            ? decodeMAPIString(htmlProp.value, baseType)
+            : decodeUtf8(htmlProp.value);
+        }
+
+        if (!result.body) {
+          const bodyProp = props.get(PR_BODY);
+          if (bodyProp?.value instanceof Uint8Array) {
+            result.body = decodeMAPIString(bodyProp.value, bodyProp.type & 0x0fff);
+          }
+        }
+      }
+    } else if (level === LVL_ATTACHMENT) {
+      if (attrID === attAttachRenddata) {
+        if (curAttach?.data) {
+          result.attachments.push({ name: curAttach.name, mimeType: curAttach.mimeType, data: curAttach.data });
+        }
+        curAttach = { name: 'attachment', mimeType: 'application/octet-stream', data: null };
+      } else if (attrID === attAttachTitle && curAttach) {
+        let len = attrData.byteLength;
+        if (len > 0 && attrData[len - 1] === 0) len--;
+        curAttach.name = decodeUtf8(attrData.subarray(0, len));
+      } else if (attrID === attAttachData && curAttach) {
+        curAttach.data = attrData;
+      } else if (attrID === attAttachment && curAttach) {
+        const props = parseMAPIProps(attrData);
+
+        const longName = props.get(PR_ATTACH_LONG_FILENAME);
+        if (longName?.value instanceof Uint8Array) {
+          curAttach.name = decodeMAPIString(longName.value, longName.type & 0x0fff);
+        }
+
+        const mimeTag = props.get(PR_ATTACH_MIME_TAG);
+        if (mimeTag?.value instanceof Uint8Array) {
+          curAttach.mimeType = decodeMAPIString(mimeTag.value, mimeTag.type & 0x0fff);
+        }
+
+        const attachData = props.get(PR_ATTACH_DATA_BIN);
+        if (attachData?.value instanceof Uint8Array) {
+          curAttach.data = attachData.value;
+        }
+      }
+    }
+  }
+
+  if (curAttach?.data) {
+    result.attachments.push({ name: curAttach.name, mimeType: curAttach.mimeType, data: curAttach.data });
+  }
+
+  return result;
+}
+
+/** Check if a MIME attachment is a TNEF (winmail.dat) file. */
+export function isTnefAttachment(name?: string | null, type?: string): boolean {
+  const lowerName = (name || '').toLowerCase();
+  const lowerType = (type || '').toLowerCase();
+  return (
+    lowerName === 'winmail.dat'
+    || lowerType === 'application/ms-tnef'
+    || lowerType === 'application/vnd.ms-tnef'
+  );
+}
diff --git a/src/screens/EmailSourceScreen.tsx b/src/screens/EmailSourceScreen.tsx
index 778a5741..39990168 100644
--- a/src/screens/EmailSourceScreen.tsx
+++ b/src/screens/EmailSourceScreen.tsx
@@ -3,23 +3,31 @@ import {
   View, Text, StyleSheet, ScrollView, ActivityIndicator, Pressable, Alert,
 } from 'react-native';
 import { SafeAreaView } from 'react-native-safe-area-context';
-import { ArrowLeft, Share2 } from 'lucide-react-native';
+import { ArrowLeft, Share2, Copy, Check } from 'lucide-react-native';
+import * as Clipboard from 'expo-clipboard';
 import type { NativeStackScreenProps } from '@react-navigation/native-stack';
 import type { RootStackParamList } from '../navigation/types';
 import { fetchRawEmail, shareEmailEml } from '../lib/email-export';
 import { spacing, typography, componentSizes, radius, type ThemePalette } from '../theme/tokens';
 import { useColors } from '../theme/colors';
+import { useLocaleStore } from '../stores/locale-store';
 
 type Props = NativeStackScreenProps<RootStackParamList, 'EmailSource'>;
 
+// A single <Text> holding a multi-megabyte string stalls the JS thread and
+// the native text layout; anything past this is offered via share instead.
+const MAX_DISPLAY_BYTES = 1024 * 1024;
+
 export default function EmailSourceScreen({ route, navigation }: Props) {
   const c = useColors();
   const styles = React.useMemo(() => makeStyles(c), [c]);
+  const t = useLocaleStore((s) => s.t);
   // Blobs are account-scoped, so a message from a shared/group mailbox has
   // to be fetched against its owning account.
   const { blobId, subject, jmapAccountId } = route.params;
   const [raw, setRaw] = React.useState<string | null>(null);
   const [error, setError] = React.useState<string | null>(null);
+  const [copied, setCopied] = React.useState(false);
 
   React.useEffect(() => {
     let cancelled = false;
@@ -28,17 +36,31 @@ export default function EmailSourceScreen({ route, navigation }: Props) {
         const text = await fetchRawEmail(blobId, jmapAccountId);
         if (!cancelled) setRaw(text);
       } catch (e) {
-        if (!cancelled) setError(e instanceof Error ? e.message : 'Failed to load email source');
+        if (!cancelled) setError(e instanceof Error ? e.message : t('email_viewer.load_failed', 'Failed to load email source'));
       }
     })();
     return () => { cancelled = true; };
-  }, [blobId, jmapAccountId]);
+  }, [blobId, jmapAccountId, t]);
+
+  const truncated = !!raw && raw.length > MAX_DISPLAY_BYTES;
+  const shown = React.useMemo(() => (raw && truncated ? raw.slice(0, MAX_DISPLAY_BYTES) : raw), [raw, truncated]);
 
   const onShare = async () => {
     try {
       await shareEmailEml(blobId, undefined, subject, jmapAccountId);
     } catch (e) {
-      Alert.alert('Share failed', e instanceof Error ? e.message : String(e));
+      Alert.alert(t('email_viewer.export_failed', 'Share failed'), e instanceof Error ? e.message : String(e));
+    }
+  };
+
+  const onCopy = async () => {
+    if (!raw) return;
+    try {
+      await Clipboard.setStringAsync(raw);
+      setCopied(true);
+      setTimeout(() => setCopied(false), 2000);
+    } catch (e) {
+      Alert.alert(t('common.error', 'Error'), e instanceof Error ? e.message : String(e));
     }
   };
 
@@ -49,8 +71,17 @@ export default function EmailSourceScreen({ route, navigation }: Props) {
           <ArrowLeft size={22} color={c.text} />
         </Pressable>
         <Text style={styles.headerTitle} numberOfLines={1}>
-          {subject || 'Email source'}
+          {subject || t('email_viewer.email_source', 'Email Source')}
         </Text>
+        <Pressable
+          onPress={onCopy}
+          style={styles.headerBtn}
+          hitSlop={8}
+          disabled={!raw}
+          accessibilityLabel={t('email_viewer.copy_source', 'Copy to clipboard')}
+        >
+          {copied ? <Check size={20} color={c.success} /> : <Copy size={20} color={raw ? c.text : c.textMuted} />}
+        </Pressable>
         <Pressable onPress={onShare} style={styles.headerBtn} hitSlop={8} disabled={!raw}>
           <Share2 size={20} color={raw ? c.text : c.textMuted} />
         </Pressable>
@@ -66,7 +97,17 @@ export default function EmailSourceScreen({ route, navigation }: Props) {
         </View>
       ) : (
         <ScrollView contentContainerStyle={styles.body}>
-          <Text selectable style={styles.source}>{raw}</Text>
+          {truncated && (
+            <View style={styles.notice}>
+              <Text style={styles.noticeText}>
+                {t('email_viewer.source_too_large', 'The message is too large to display in full. Share the full source instead.')}
+              </Text>
+              <Pressable onPress={onShare} hitSlop={6}>
+                <Text style={styles.noticeAction}>{t('email_viewer.export_email', 'Export as .eml')}</Text>
+              </Pressable>
+            </View>
+          )}
+          <Text selectable style={styles.source}>{shown}</Text>
         </ScrollView>
       )}
     </SafeAreaView>
@@ -92,6 +133,15 @@ function makeStyles(c: ThemePalette) {
   loading: { flex: 1, alignItems: 'center', justifyContent: 'center' },
   error: { ...typography.body, color: c.error, paddingHorizontal: spacing.lg, textAlign: 'center' },
   body: { padding: spacing.lg },
+  notice: {
+    marginBottom: spacing.md,
+    padding: spacing.md,
+    borderRadius: radius.md,
+    backgroundColor: c.warningBg,
+    gap: spacing.xs,
+  },
+  noticeText: { ...typography.caption, color: c.warning },
+  noticeAction: { ...typography.caption, color: c.primary, fontWeight: '600' },
   source: {
     fontFamily: 'monospace',
     fontSize: 11,
diff --git a/src/screens/EmailThreadScreen.tsx b/src/screens/EmailThreadScreen.tsx
index dda40c73..90c33591 100644
--- a/src/screens/EmailThreadScreen.tsx
+++ b/src/screens/EmailThreadScreen.tsx
@@ -8,16 +8,17 @@ import { SafeAreaView, useSafeAreaInsets } from 'react-native-safe-area-context'
 import type { NativeStackScreenProps } from '@react-navigation/native-stack';
 import {
   ArrowLeft, Star, Trash2, MoreVertical, Reply, ReplyAll, Forward,
-  ChevronLeft, ChevronRight, Paperclip, Archive, Mail, MailOpen,
+  ChevronLeft, ChevronRight, Archive, Mail, MailOpen,
   FolderInput, ShieldAlert, ShieldCheck, X, Check,
-  Code, Download, Tag,
+  Code, Download, Tag, Sun, Moon, FileInput, UserRoundPlus,
 } from 'lucide-react-native';
 import { spacing, radius, typography, componentSizes, type ThemePalette } from '../theme/tokens';
-import { useColors } from '../theme/colors';
-import EmailBodyView from '../components/EmailBodyView';
-import { CalendarInvitationBanner } from '../components/email/CalendarInvitationBanner';
-import SenderAvatar from '../components/SenderAvatar';
+import { useColors, useResolvedTheme } from '../theme/colors';
 import { MoveSheet } from '../components/MoveSheet';
+import { MessageContent } from '../components/email/MessageContent';
+import { ThreadMessageCard } from '../components/email/ThreadMessageCard';
+import { QuickReplyBox } from '../components/email/QuickReplyBox';
+import { AddressActionSheet } from '../components/email/AddressActionSheet';
 import { useEmailStore } from '../stores/email-store';
 import {
   useSettingsStore,
@@ -25,45 +26,19 @@ import {
   REPLY_QUICK_ACTIONS,
   type QuickAction,
 } from '../stores/settings-store';
-import { setEmailKeywords } from '../api/email';
-import { shareEmailEml, shareAttachment, downloadAttachment } from '../lib/email-export';
+import { setEmailKeywords, getThreadEmails } from '../api/email';
+import { shareEmailEml } from '../lib/email-export';
 import { useKeywordsStore, keywordToken, type KeywordDef } from '../stores/keywords-store';
 import { useSheetDrag } from '../lib/use-sheet-drag';
 import { useLocaleStore } from '../stores/locale-store';
 import { findTrashMailbox, mailboxesForSiblingOf } from '../lib/mailbox-tree';
-import type { Email, Mailbox } from '../api/types';
+import { pickEmailBody, plainTextBody } from '../lib/email-body';
+import { buildForwardAsAttachmentPayload } from '../lib/forward-as-attachment';
+import type { Email, EmailAddress, Identity } from '../api/types';
 import type { RootStackParamList } from '../navigation/types';
 
 type Props = NativeStackScreenProps<RootStackParamList, 'EmailThread'>;
 
-function formatHeaderDate(iso: string): string {
-  const d = new Date(iso);
-  return d.toLocaleDateString(undefined, {
-    weekday: 'short', year: 'numeric', month: 'short', day: 'numeric',
-  });
-}
-
-function formatHeaderTime(iso: string): string {
-  return new Date(iso).toLocaleTimeString(undefined, {
-    hour: '2-digit', minute: '2-digit',
-  });
-}
-
-function formatSize(bytes?: number): string {
-  if (!bytes) return '';
-  if (bytes < 1024) return `${bytes} B`;
-  if (bytes < 1024 * 1024) return `${(bytes / 1024).toFixed(2)} KB`;
-  return `${(bytes / (1024 * 1024)).toFixed(2)} MB`;
-}
-
-function plainTextBody(email: Email): string {
-  const textPart = email.textBody?.[0];
-  if (textPart?.partId && email.bodyValues?.[textPart.partId]?.value) {
-    return email.bodyValues[textPart.partId].value;
-  }
-  return email.preview ?? '';
-}
-
 export default function EmailThreadScreen({ route, navigation }: Props) {
   const c = useColors();
   const styles = React.useMemo(() => makeStyles(c), [c]);
@@ -83,21 +58,48 @@ export default function EmailThreadScreen({ route, navigation }: Props) {
   const mailboxes = useEmailStore((s) => s.mailboxes);
   const currentMailboxId = useEmailStore((s) => s.currentMailboxId);
   const storeEmails = useEmailStore((s) => s.emails);
+  const disableThreading = useSettingsStore((s) => s.disableThreading);
+  const identities = useSettingsStore((s) => s.identities);
+  const fetchIdentities = useSettingsStore((s) => s.fetchIdentities);
+  const deleteAction = useSettingsStore((s) => s.deleteAction);
+  const permanentlyDeleteJunk = useSettingsStore((s) => s.permanentlyDeleteJunk);
+  const postExportAction = useSettingsStore((s) => s.postExportAction);
+  const emailAlwaysLightMode = useSettingsStore((s) => s.emailAlwaysLightMode);
+  const exportSpaceReplacement = useSettingsStore((s) => s.exportSpaceReplacement);
+  const exportLowercase = useSettingsStore((s) => s.exportLowercase);
+  const exportStripDiacritics = useSettingsStore((s) => s.exportStripDiacritics);
+  const resolvedTheme = useResolvedTheme();
+  React.useEffect(() => { if (identities.length === 0) void fetchIdentities(); }, [identities.length, fetchIdentities]);
+
   // The list the pager pages over. A message opened from the active folder
-  // pages over that folder; one opened from another list (unified inbox,
-  // contact activity) pages over the ids that list handed us, and a message
-  // that is in neither (e.g. a group-inbox message not in the folder page)
-  // gets a one-element list — otherwise the pager would render `emails[0]`
-  // while the toolbar acted on the tapped message.
+  // pages over that folder (collapsed to one page per thread when threading
+  // is on, the opened message standing in for its thread); one opened from
+  // another list (unified inbox, contact activity) pages over the ids that
+  // list handed us, and a message that is in neither (e.g. a group-inbox
+  // message not in the folder page) gets a one-element list — otherwise the
+  // pager would render `emails[0]` while the toolbar acted on the tapped one.
   const emails = React.useMemo<Email[]>(() => {
     const { emailIds, emailId, threadId } = route.params;
     if (emailIds && emailIds.length > 0) {
       const byId = jmapAccountId ? null : new Map(storeEmails.map((e) => [e.id, e]));
       return emailIds.map((id) => byId?.get(id) ?? ({ id, threadId } as Email));
     }
-    if (!jmapAccountId && storeEmails.some((e) => e.id === emailId)) return storeEmails;
+    const opened = jmapAccountId ? undefined : storeEmails.find((e) => e.id === emailId);
+    if (opened) {
+      if (disableThreading) return storeEmails;
+      const openedKey = opened.threadId || opened.id;
+      const seen = new Set<string>();
+      const out: Email[] = [];
+      for (const e of storeEmails) {
+        const key = e.threadId || e.id;
+        if (seen.has(key)) continue;
+        seen.add(key);
+        out.push(key === openedKey ? opened : e);
+      }
+      return out;
+    }
     return [{ id: emailId, threadId } as Email];
-  }, [storeEmails, route.params, jmapAccountId]);
+  }, [storeEmails, route.params, jmapAccountId, disableThreading]);
 
   // The JMAP account the open message belongs to: the route param when the
   // unified inbox opened a group message, otherwise the account behind the
@@ -109,6 +111,10 @@ export default function EmailThreadScreen({ route, navigation }: Props) {
       : undefined;
     return current?.isShared ? current.accountId : undefined;
   }, [jmapAccountId, mailboxes, currentMailboxId]);
+  const currentMailboxRole = React.useMemo(
+    () => (currentMailboxId ? mailboxes.find((m) => m.id === currentMailboxId)?.role ?? null : null),
+    [mailboxes, currentMailboxId],
+  );
 
   const currentIndex = emails.findIndex((e) => e.id === activeEmailId);
   const prevEmail = currentIndex > 0 ? emails[currentIndex - 1] : null;
@@ -118,7 +124,9 @@ export default function EmailThreadScreen({ route, navigation }: Props) {
   const [moreMenuOpen, setMoreMenuOpen] = React.useState(false);
   const [moveMenuOpen, setMoveMenuOpen] = React.useState(false);
   const [tagMenuOpen, setTagMenuOpen] = React.useState(false);
-  const [downloadingBlobId, setDownloadingBlobId] = React.useState<string | null>(null);
+  const [addressSheet, setAddressSheet] = React.useState<EmailAddress | null>(null);
+  // Per-message override of the light/dark rendering (More sheet toggle).
+  const [themeOverrides, setThemeOverrides] = React.useState<Record<string, 'light' | 'dark'>>({});
 
   // In-memory cache of fetched message details keyed by id. This is the single
   // source of truth for every rendered pane: the active message *and* its
@@ -126,6 +134,8 @@ export default function EmailThreadScreen({ route, navigation }: Props) {
   // ready content with no spinner and no late content-swap. `cacheVersion` is
   // bumped whenever an entry changes so the panes re-render.
   const detailCache = React.useRef(new Map<string, Email>()).current;
+  // Thread id -> message ids (oldest first), once the conversation was fetched.
+  const threadCache = React.useRef(new Map<string, string[]>()).current;
   const [cacheVersion, setCacheVersion] = React.useState(0);
   const bumpCache = React.useCallback(() => setCacheVersion((v) => v + 1), []);
   const email = React.useMemo(
@@ -135,14 +145,11 @@ export default function EmailThreadScreen({ route, navigation }: Props) {
   );
 
   // --- Pager -------------------------------------------------------------
-  // The pager is a horizontal, page-snapping FlatList over the mailbox's
-  // `emails`. Native scroll provides the swipe + snap (and plays nicely with
-  // each pane's vertical body scroll); Prev/Next scroll programmatically. When
-  // scrolling settles, the centred page's id becomes `activeEmailId`, which is
-  // what the toolbar and action handlers operate on.
+  // A horizontal, page-snapping FlatList over `emails`. Native scroll provides
+  // the swipe + snap; Prev/Next scroll programmatically. When scrolling
+  // settles, the centred page's id becomes `activeEmailId`, which is what the
+  // toolbar and action handlers operate on.
   const listRef = React.useRef<FlatList<Email>>(null);
-  // The page to open on mount — the entry point arrives as a route param, so
-  // capture its index once.
   const initialIndexRef = React.useRef(
     Math.max(0, emails.findIndex((e) => e.id === route.params.emailId)),
   );
@@ -162,8 +169,35 @@ export default function EmailThreadScreen({ route, navigation }: Props) {
     return p;
   }, [getEmailDetail, ownerAccountId, detailCache, bumpCache, inFlight]);
 
-  // Slide to a page by index and reflect it in the toolbar immediately; a swipe
-  // that settles on the same page confirms the same id via onMomentumEnd.
+  // Whole conversation (Thread/get -> Email/get), cached per thread id. Every
+  // message lands in the detail cache so the cards render straight from it.
+  const threadInFlight = React.useRef(new Map<string, Promise<string[]>>()).current;
+  const ensureThread = React.useCallback((threadId: string): Promise<string[]> => {
+    const cached = threadCache.get(threadId);
+    if (cached) return Promise.resolve(cached);
+    const pending = threadInFlight.get(threadId);
+    if (pending) return pending;
+    const p = getThreadEmails(threadId, ownerAccountId)
+      .then((list) => {
+        for (const e of list) detailCache.set(e.id, e);
+        const ids = list.map((e) => e.id);
+        threadCache.set(threadId, ids);
+        bumpCache();
+        return ids;
+      })
+      .catch((err) => {
+        console.warn('[thread] fetch failed', err);
+        // Fall back to the single message so the pane still renders.
+        const single = detailCache.has(activeEmailId) ? [activeEmailId] : [];
+        threadCache.set(threadId, single);
+        bumpCache();
+        return single;
+      })
+      .finally(() => { threadInFlight.delete(threadId); });
+    threadInFlight.set(threadId, p);
+    return p;
+  }, [ownerAccountId, detailCache, threadCache, bumpCache, threadInFlight, activeEmailId]);
+
   const goToIndex = React.useCallback((index: number) => {
     if (index < 0 || index >= emails.length) return;
     listRef.current?.scrollToOffset({ offset: index * windowWidth, animated: true });
@@ -171,33 +205,24 @@ export default function EmailThreadScreen({ route, navigation }: Props) {
     if (target) setActiveEmailId(target.id);
   }, [emails, windowWidth]);
 
-  // Adopt the centred page as the active message once a swipe settles.
   const onMomentumEnd = React.useCallback((e: NativeSyntheticEvent<NativeScrollEvent>) => {
     const index = Math.round(e.nativeEvent.contentOffset.x / windowWidth);
     const target = emails[index];
     if (target && target.id !== activeEmailId) setActiveEmailId(target.id);
   }, [emails, windowWidth, activeEmailId]);
 
-  // Page offsets are in window-width units, so a rotation / resize invalidates
-  // the scroll position — re-centre the active page after the width changes.
   React.useLayoutEffect(() => {
     const index = emails.findIndex((e) => e.id === activeEmailId);
     if (index >= 0) listRef.current?.scrollToOffset({ offset: index * windowWidth, animated: false });
     // eslint-disable-next-line react-hooks/exhaustive-deps
   }, [windowWidth]);
 
-  // While the body is pinch-zoomed (or a pinch is in flight) horizontal
-  // gestures pan the zoomed content, so the pager must not treat them as page
-  // swipes. Prev/Next stay usable: programmatic scrollToOffset ignores
-  // scrollEnabled. Reset when the active message changes — the zoomed pane's
-  // WebView can unmount without reporting back.
+  // While the body is pinch-zoomed the pager must not treat horizontal
+  // gestures as page swipes.
   const [pagerLocked, setPagerLocked] = React.useState(false);
   React.useEffect(() => { setPagerLocked(false); }, [activeEmailId]);
 
-  const mailAttachmentAction = useSettingsStore((s) => s.mailAttachmentAction);
-  const attachmentPosition = useSettingsStore((s) => s.attachmentPosition);
   const markAsReadDelay = useSettingsStore((s) => s.markAsReadDelay);
-  const hideInlineImageAttachments = useSettingsStore((s) => s.hideInlineImageAttachments);
   const bottomQuickActionsRaw = useSettingsStore((s) => s.bottomQuickActions);
   const bottomActions = React.useMemo(
     () => normalizeBottomQuickActions(bottomQuickActionsRaw),
@@ -210,67 +235,62 @@ export default function EmailThreadScreen({ route, navigation }: Props) {
     [bottomActions],
   );
 
-  const onPressAttachment = React.useCallback(
-    async (target: Email, blobId: string, name: string | undefined, type: string | undefined) => {
-      if (downloadingBlobId) return;
-      setDownloadingBlobId(blobId);
-      try {
-        if (mailAttachmentAction === 'download') {
-          await downloadAttachment(blobId, name, type, target, ownerAccountId);
-        } else {
-          await shareAttachment(blobId, name, type, target, ownerAccountId);
-        }
-      } catch (e) {
-        Alert.alert('Download failed', e instanceof Error ? e.message : String(e));
-      } finally {
-        setDownloadingBlobId(null);
-      }
-    },
-    [downloadingBlobId, mailAttachmentAction, ownerAccountId],
-  );
   const keywordDefs = useKeywordsStore((s) => s.keywords);
   const hydrateKeywords = useKeywordsStore((s) => s.hydrate);
   const keywordsHydrated = useKeywordsStore((s) => s.hydrated);
   React.useEffect(() => { if (!keywordsHydrated) void hydrateKeywords(); }, [keywordsHydrated, hydrateKeywords]);
 
+  // Optimistically write a message's keywords into the cache (the single source
+  // of truth for every pane) and bump the version so the panes re-render.
+  const updateLocalKeywords = React.useCallback((id: string, next: Record<string, boolean>) => {
+    const prev = detailCache.get(id);
+    if (!prev) return;
+    detailCache.set(id, { ...prev, keywords: next });
+    bumpCache();
+  }, [detailCache, bumpCache]);
+
+  // Mark a message read per the user's delay setting: -1 never, 0 instantly,
+  // >0 after that many milliseconds. Returns a cancel function.
+  const scheduleMarkRead = React.useCallback((target: Email): (() => void) => {
+    if (target.keywords?.$seen || markAsReadDelay === -1) return () => undefined;
+    const apply = () => {
+      updateLocalKeywords(target.id, { ...target.keywords, $seen: true });
+      void markRead(target.id, ownerAccountId);
+    };
+    if (markAsReadDelay > 0) {
+      const timer = setTimeout(apply, markAsReadDelay);
+      return () => clearTimeout(timer);
+    }
+    apply();
+    return () => undefined;
+  }, [markAsReadDelay, markRead, ownerAccountId, updateLocalKeywords]);
+
   React.useEffect(() => {
     let cancelled = false;
-    let readTimer: ReturnType<typeof setTimeout> | null = null;
-    // Refresh the active message — a cached copy (the pane may have fetched it,
-    // or it was visited before) renders immediately while this lands. Then mark
-    // it read per the user's delay. The pane itself fetches its own detail, so
-    // ensureDetail here usually rides the same in-flight request.
+    let cancelRead: (() => void) | null = null;
+    // Refresh the active message — a cached copy renders immediately while
+    // this lands. Then mark it read per the user's delay.
     setError(null);
     void (async () => {
       const fetched = await ensureDetail(activeEmailId);
       if (cancelled) return;
       if (!fetched) {
-        // Only surface an error if there's nothing cached to show.
-        if (!detailCache.has(activeEmailId)) setError('Failed to load email');
+        if (!detailCache.has(activeEmailId)) setError(t('email_viewer.load_failed', 'Failed to load email'));
         return;
       }
-      if (!fetched.keywords?.$seen) {
-        if (markAsReadDelay > 0) {
-          readTimer = setTimeout(() => {
-            if (!cancelled) void markRead(activeEmailId, ownerAccountId);
-          }, markAsReadDelay);
-        } else {
-          void markRead(activeEmailId, ownerAccountId);
-        }
-      }
+      cancelRead = scheduleMarkRead(fetched);
     })();
     return () => {
       cancelled = true;
-      if (readTimer) clearTimeout(readTimer);
+      cancelRead?.();
     };
-  }, [activeEmailId, ensureDetail, markRead, markAsReadDelay, ownerAccountId, detailCache]);
+  }, [activeEmailId, ensureDetail, scheduleMarkRead, detailCache, t]);
 
   const starred = !!email?.keywords?.$flagged;
   const unread = !!email && !email.keywords?.$seen;
 
   // Move/archive/spam targets have to live in the same account as the folder
-  // the message was opened from — a shared (group account) message can't be
-  // filed into the user's own folders.
+  // the message was opened from.
   const scopedMailboxes = React.useMemo(
     () => mailboxesForSiblingOf(mailboxes, currentMailboxId),
     [mailboxes, currentMailboxId],
@@ -290,15 +310,8 @@ export default function EmailThreadScreen({ route, navigation }: Props) {
   // `mailboxIds` comes back from the server unprefixed, so compare on the
   // folder's raw id rather than the sidebar key.
   const isInJunk = !!(junkMailbox && email?.mailboxIds?.[junkMailbox.originalId ?? junkMailbox.id]);
-
-  // Optimistically write a message's keywords into the cache (the single source
-  // of truth for every pane) and bump the version so the panes re-render.
-  const updateLocalKeywords = (id: string, next: Record<string, boolean>) => {
-    const prev = detailCache.get(id);
-    if (!prev) return;
-    detailCache.set(id, { ...prev, keywords: next });
-    bumpCache();
-  };
+  const trashMailbox = React.useMemo(() => findTrashMailbox(scopedMailboxes), [scopedMailboxes]);
+  const isInTrash = !!(trashMailbox && currentMailboxId === trashMailbox.id);
 
   const onToggleKeyword = (token: string) => {
     if (!email) return;
@@ -310,15 +323,14 @@ export default function EmailThreadScreen({ route, navigation }: Props) {
   };
 
   // Toggle the star on a specific message — used both by the toolbar (current
-  // message) and by each pane's own subject star.
+  // message) and by each pane's own subject star / card header.
   const toggleStarFor = React.useCallback((target: Email) => {
     const next = { ...target.keywords };
     if (next.$flagged) delete next.$flagged;
     else next.$flagged = true;
-    const prev = detailCache.get(target.id);
-    if (prev) { detailCache.set(target.id, { ...prev, keywords: next }); bumpCache(); }
+    updateLocalKeywords(target.id, next);
     void setEmailKeywords(target.id, next, ownerAccountId);
-  }, [detailCache, bumpCache, ownerAccountId]);
+  }, [updateLocalKeywords, ownerAccountId]);
 
   const onToggleStar = () => { if (email) toggleStarFor(email); };
 
@@ -335,18 +347,42 @@ export default function EmailThreadScreen({ route, navigation }: Props) {
     }
   };
 
+  const onEmailPatched = React.useCallback((patched: Email) => {
+    detailCache.set(patched.id, patched);
+    bumpCache();
+  }, [detailCache, bumpCache]);
+
+  const performDelete = () => {
+    if (!email || !currentMailboxId || !trashMailbox) return;
+    void deleteEmail(email.id, trashMailbox.id, currentMailboxId);
+    navigation.goBack();
+  };
+
   const onDelete = () => {
     if (!email || !currentMailboxId) return;
-    const trash = findTrashMailbox(scopedMailboxes);
-    if (!trash) {
+    if (!trashMailbox) {
       Alert.alert(
         t('email_list.error', 'Error'),
         t('email_list.no_trash_folder', 'Could not find a Trash folder on the server. Please check your mailbox configuration.'),
       );
       return;
     }
-    void deleteEmail(email.id, trash.id, currentMailboxId);
-    navigation.goBack();
+    // The store destroys (instead of moving) in trash, for junk when the user
+    // opted to skip the trash, and when the delete action is "permanent" -
+    // none of those can be undone, so confirm first.
+    const permanent = isInTrash || deleteAction === 'permanent' || (permanentlyDeleteJunk && isInJunk);
+    if (permanent) {
+      Alert.alert(
+        t('email_viewer.delete_permanently_title', 'Delete permanently?'),
+        t('email_viewer.delete_permanently_message', 'This message will be deleted permanently and cannot be recovered.'),
+        [
+          { text: t('common.cancel', 'Cancel'), style: 'cancel' },
+          { text: t('common.delete', 'Delete'), style: 'destructive', onPress: performDelete },
+        ],
+      );
+      return;
+    }
+    performDelete();
   };
 
   const onArchive = () => {
@@ -378,43 +414,63 @@ export default function EmailThreadScreen({ route, navigation }: Props) {
     navigation.goBack();
   };
 
-  const navigateCompose = (mode: 'reply' | 'replyAll' | 'forward') => {
-    if (!email) return;
-    const from = email.from?.[0];
+  // Reply / forward the given message (a thread card's own, or the active one).
+  const navigateCompose = React.useCallback((mode: 'reply' | 'replyAll' | 'forward', target?: Email) => {
+    const source = target ?? email;
+    if (!source) return;
+    const from = source.from?.[0];
     if (!from && mode !== 'forward') return;
     // Quote the HTML part when there is one so layout and inline images
     // survive (#163). RFC 8621 §4.1.4: an HTML-only message exposes the same
     // part in `textBody` and `htmlBody`, so the text part is only a real
-    // alternative when its partId differs - otherwise `plainTextBody` would
-    // hand the composer raw HTML source (#649).
-    const htmlPart = email.htmlBody?.[0];
-    const textPart = email.textBody?.[0];
-    const htmlValue = htmlPart?.partId ? email.bodyValues?.[htmlPart.partId]?.value : undefined;
-    const htmlIsHtml = !htmlPart?.type || /text\/html/i.test(htmlPart.type);
-    const quoteHtml = htmlValue && htmlIsHtml ? htmlValue : undefined;
-    const hasDistinctText = !!textPart?.partId && textPart.partId !== htmlPart?.partId;
-    const body = !quoteHtml || hasDistinctText ? plainTextBody(email) : undefined;
+    // alternative when its partId differs - otherwise the composer would be
+    // handed raw HTML source (#649, native #46).
+    const picked = pickEmailBody(source);
+    const quoteHtml = picked.html ?? undefined;
+    const body = !quoteHtml || picked.text ? plainTextBody(source) : undefined;
     navigation.navigate('Compose', {
       mode,
       replyTo: {
         from: from ?? { email: '' },
-        to: email.to,
-        cc: email.cc,
+        to: source.to,
+        cc: source.cc,
         // RFC 5322: a reply goes to Reply-To when the sender set one.
-        replyToAddresses: email.replyTo,
-        subject: email.subject ?? '',
+        replyToAddresses: source.replyTo,
+        subject: source.subject ?? '',
         body,
         htmlBody: quoteHtml,
-        receivedAt: email.receivedAt,
-        sentAt: email.sentAt,
+        receivedAt: source.receivedAt,
+        sentAt: source.sentAt,
         // Threading needs the RFC Message-ID, never the JMAP object id (#234).
-        messageId: email.messageId ?? undefined,
-        references: email.references ?? undefined,
+        messageId: source.messageId ?? undefined,
+        references: source.references ?? undefined,
         // Forward carries the original attachments as blob refs; cid-embedded
         // inline images are already part of the quoted HTML.
         attachments: mode === 'forward'
-          ? (email.attachments ?? []).filter((a) => !(a.disposition === 'inline' && a.cid))
+          ? (source.attachments ?? []).filter((a) => !(a.disposition === 'inline' && a.cid))
           : undefined,
+        originalEmailId: source.id,
+        jmapAccountId: ownerAccountId,
+      },
+    });
+  }, [email, navigation, ownerAccountId]);
+
+  // Forward the raw message as a message/rfc822 attachment (webmail 1.8.1).
+  const onForwardAsAttachment = () => {
+    setMoreMenuOpen(false);
+    if (!email) return;
+    const payload = buildForwardAsAttachmentPayload(
+      email,
+      t('email_composer.prefix.forward', 'Fwd:'),
+      { spaceReplacement: exportSpaceReplacement, lowercase: exportLowercase, stripDiacritics: exportStripDiacritics },
+    );
+    if (!payload) return;
+    navigation.navigate('Compose', {
+      mode: 'forward',
+      replyTo: {
+        from: email.from?.[0] ?? { email: '' },
+        subject: email.subject ?? '',
+        attachments: [payload.attachment],
         originalEmailId: email.id,
         jmapAccountId: ownerAccountId,
       },
@@ -422,50 +478,49 @@ export default function EmailThreadScreen({ route, navigation }: Props) {
   };
 
   // Registry of every action that can live in the bottom quick-action bar (or
-  // be relocated to the top toolbar). `icon` is a factory so the same action
-  // can render at the toolbar (18px) and bottom-bar (20px) sizes.
+  // be relocated to the top toolbar).
   const quickActionRegistry: Record<
     QuickAction,
     { label: string; icon: (size: number, color: string) => React.ReactNode; onPress: () => void; available: boolean }
   > = {
     reply: {
-      label: 'Reply',
+      label: t('email_viewer.reply', 'Reply'),
       icon: (s, col) => <Reply size={s} color={col} />,
       onPress: () => navigateCompose('reply'),
       available: true,
     },
     replyAll: {
-      label: 'Reply All',
+      label: t('email_viewer.reply_all', 'Reply All'),
       icon: (s, col) => <ReplyAll size={s} color={col} />,
       onPress: () => navigateCompose('replyAll'),
       available: true,
     },
     forward: {
-      label: 'Forward',
+      label: t('email_viewer.forward', 'Forward'),
       icon: (s, col) => <Forward size={s} color={col} />,
       onPress: () => navigateCompose('forward'),
       available: true,
     },
     delete: {
-      label: 'Delete',
+      label: t('email_viewer.delete', 'Delete'),
       icon: (s, col) => <Trash2 size={s} color={col} />,
       onPress: onDelete,
       available: true,
     },
     archive: {
-      label: 'Archive',
+      label: t('email_viewer.archive', 'Archive'),
       icon: (s, col) => <Archive size={s} color={col} />,
       onPress: onArchive,
       available: !!archiveMailbox && currentMailboxId !== archiveMailbox?.id,
     },
     markUnread: {
-      label: unread ? 'Read' : 'Unread',
+      label: unread ? t('email_viewer.read', 'Read') : t('email_viewer.unread', 'Unread'),
       icon: (s, col) => (unread ? <MailOpen size={s} color={col} /> : <Mail size={s} color={col} />),
       onPress: onToggleUnread,
       available: true,
     },
     star: {
-      label: starred ? 'Unstar' : 'Star',
+      label: starred ? t('email_viewer.unstar', 'Unstar') : t('email_viewer.star', 'Star'),
       icon: (s, col) => (
         <Star size={s} color={starred ? c.starred : col} fill={starred ? c.starred : 'transparent'} />
       ),
@@ -473,20 +528,20 @@ export default function EmailThreadScreen({ route, navigation }: Props) {
       available: true,
     },
     move: {
-      label: 'Move',
+      label: t('email_viewer.move', 'Move'),
       icon: (s, col) => <FolderInput size={s} color={col} />,
       onPress: () => setMoveMenuOpen(true),
       available: mailboxes.length > 0,
     },
     spam: {
-      label: isInJunk ? 'Not spam' : 'Spam',
+      label: isInJunk ? t('email_viewer.not_spam_short', 'Not spam') : t('email_viewer.spam_short', 'Spam'),
       icon: (s, col) =>
         isInJunk ? <ShieldCheck size={s} color={c.success} /> : <ShieldAlert size={s} color={col} />,
       onPress: onToggleSpam,
       available: !!junkMailbox || isInJunk,
     },
     tag: {
-      label: 'Tag',
+      label: t('email_viewer.tag', 'Tag'),
       icon: (s, col) => <Tag size={s} color={col} />,
       onPress: () => setTagMenuOpen(true),
       available: keywordDefs.length > 0,
@@ -494,12 +549,15 @@ export default function EmailThreadScreen({ route, navigation }: Props) {
   };
 
   const bottomBarHeight = 60 + Math.max(insets.bottom, 4);
-
-  // Show extras in priority order. Each toolbar button is ~64px wide (icon+label+padding);
-  // back arrow + side padding reserves ~64px. Drop optional buttons on narrow screens.
+  // Drop optional toolbar buttons on narrow screens.
   const showMarkUnread = windowWidth >= 340;
   const showArchive = windowWidth >= 400 && !!archiveMailbox;
 
+  // Current rendering mode of the active message, for the More sheet label.
+  const activeRenderDark = email
+    ? (themeOverrides[email.id] ? themeOverrides[email.id] === 'dark' : !emailAlwaysLightMode && resolvedTheme === 'dark')
+    : false;
+
   return (
     <SafeAreaView style={styles.container} edges={['top']}>
       {/* Toolbar */}
@@ -521,13 +579,13 @@ export default function EmailThreadScreen({ route, navigation }: Props) {
           })}
           <ToolbarButton
             icon={<Trash2 size={18} color={c.textSecondary} />}
-            label="Delete"
+            label={t('email_viewer.delete', 'Delete')}
             onPress={onDelete}
           />
           {showArchive && (
             <ToolbarButton
               icon={<Archive size={18} color={c.textSecondary} />}
-              label="Archive"
+              label={t('email_viewer.archive', 'Archive')}
               onPress={onArchive}
             />
           )}
@@ -540,7 +598,7 @@ export default function EmailThreadScreen({ route, navigation }: Props) {
                   <Mail size={18} color={c.textSecondary} />
                 )
               }
-              label={unread ? 'Read' : 'Unread'}
+              label={unread ? t('email_viewer.read', 'Read') : t('email_viewer.unread', 'Unread')}
               onPress={onToggleUnread}
             />
           )}
@@ -552,12 +610,12 @@ export default function EmailThreadScreen({ route, navigation }: Props) {
                 fill={starred ? c.starred : 'transparent'}
               />
             }
-            label="Star"
+            label={t('email_viewer.star', 'Star')}
             onPress={onToggleStar}
           />
           <ToolbarButton
             icon={<MoreVertical size={18} color={c.textSecondary} />}
-            label="More"
+            label={t('email_viewer.more', 'More')}
             onPress={() => setMoreMenuOpen(true)}
           />
         </View>
@@ -569,9 +627,6 @@ export default function EmailThreadScreen({ route, navigation }: Props) {
         </View>
       ) : (
         <>
-          {/* Pager: a horizontal page-snapping list over the mailbox. Each
-              page is the full-width pane for one message; native scroll slides
-              between them and onMomentumEnd reports the settled page. */}
           <FlatList
             ref={listRef}
             style={styles.pagerViewport}
@@ -593,17 +648,28 @@ export default function EmailThreadScreen({ route, navigation }: Props) {
               <View style={{ width: windowWidth }}>
                 <EmailPane
                   id={item.id}
+                  threadIdHint={item.threadId}
                   email={detailCache.get(item.id) ?? null}
+                  detailCache={detailCache}
+                  threadIds={
+                    !disableThreading
+                      ? threadCache.get(detailCache.get(item.id)?.threadId ?? item.threadId) ?? null
+                      : null
+                  }
+                  threading={!disableThreading}
                   jmapAccountId={ownerAccountId}
+                  currentMailboxRole={currentMailboxRole}
+                  identities={identities}
+                  themeOverrides={themeOverrides}
                   ensureDetail={ensureDetail}
-                  c={c}
+                  ensureThread={ensureThread}
+                  scheduleMarkRead={scheduleMarkRead}
                   styles={styles}
                   bottomBarHeight={bottomBarHeight}
-                  attachmentPosition={attachmentPosition}
-                  hideInlineImageAttachments={hideInlineImageAttachments}
-                  downloadingBlobId={downloadingBlobId}
                   onToggleStar={toggleStarFor}
-                  onPressAttachment={onPressAttachment}
+                  onAddressPress={setAddressSheet}
+                  onEmailPatched={onEmailPatched}
+                  onReply={navigateCompose}
                   onSwipe={(dir) => goToIndex(dir === 'next' ? index + 1 : index - 1)}
                   onZoomChange={(z) => setPagerLocked(z.pinching || z.zoomed)}
                 />
@@ -615,7 +681,7 @@ export default function EmailThreadScreen({ route, navigation }: Props) {
           <View style={[styles.bottomBar, { paddingBottom: Math.max(insets.bottom, 4) }]}>
             <BottomBarButton
               icon={<ChevronLeft size={20} color={c.textMuted} />}
-              label="Prev"
+              label={t('email_viewer.previous', 'Prev')}
               onPress={prevEmail ? () => goToIndex(currentIndex - 1) : undefined}
               disabled={!prevEmail}
             />
@@ -633,7 +699,7 @@ export default function EmailThreadScreen({ route, navigation }: Props) {
             })}
             <BottomBarButton
               icon={<ChevronRight size={20} color={c.textMuted} />}
-              label="Next"
+              label={t('email_viewer.next', 'Next')}
               onPress={nextEmail ? () => goToIndex(currentIndex + 1) : undefined}
               disabled={!nextEmail}
             />
@@ -653,11 +719,24 @@ export default function EmailThreadScreen({ route, navigation }: Props) {
         canViewSource={!!email?.blobId}
         canExport={!!email?.blobId}
         canTag={keywordDefs.length > 0}
+        renderDark={activeRenderDark}
+        hasSender={!!email?.from?.[0]?.email}
         onArchive={() => { setMoreMenuOpen(false); onArchive(); }}
         onToggleUnread={() => { setMoreMenuOpen(false); onToggleUnread(); }}
         onMove={() => { setMoreMenuOpen(false); setMoveMenuOpen(true); }}
         onTag={() => { setMoreMenuOpen(false); setTagMenuOpen(true); }}
         onToggleSpam={onToggleSpam}
+        onToggleTheme={() => {
+          setMoreMenuOpen(false);
+          if (!email) return;
+          setThemeOverrides((prev) => ({ ...prev, [email.id]: activeRenderDark ? 'light' : 'dark' }));
+        }}
+        onSenderActions={() => {
+          setMoreMenuOpen(false);
+          const from = email?.from?.[0];
+          if (from) setAddressSheet(from);
+        }}
+        onForwardAsAttachment={onForwardAsAttachment}
         onViewSource={() => {
           setMoreMenuOpen(false);
           if (email?.blobId) {
@@ -675,8 +754,13 @@ export default function EmailThreadScreen({ route, navigation }: Props) {
           try {
             await shareEmailEml(email.blobId, email, undefined, ownerAccountId);
           } catch (e) {
-            Alert.alert('Export failed', e instanceof Error ? e.message : String(e));
+            Alert.alert(t('email_viewer.export_failed', 'Export failed'), e instanceof Error ? e.message : String(e));
+            return;
           }
+          // Post-export action (webmail `postExportAction`): file the message
+          // away once the export is out.
+          if (postExportAction === 'archive') onArchive();
+          else if (postExportAction === 'trash') onDelete();
         }}
       />
 
@@ -695,118 +779,105 @@ export default function EmailThreadScreen({ route, navigation }: Props) {
         activeKeywords={email?.keywords ?? {}}
         onToggle={onToggleKeyword}
       />
+
+      <AddressActionSheet address={addressSheet} onClose={() => setAddressSheet(null)} />
     </SafeAreaView>
   );
 }
 
 interface EmailPaneProps {
   id: string;
+  threadIdHint?: string;
   email: Email | null;
-  /** Owning account when the message lives in a shared/group mailbox. */
+  detailCache: Map<string, Email>;
+  /** Ids of the whole conversation (oldest first) once fetched; null = not (yet) loaded. */
+  threadIds: string[] | null;
+  threading: boolean;
   jmapAccountId?: string;
+  currentMailboxRole: string | null;
+  identities: Identity[];
+  themeOverrides: Record<string, 'light' | 'dark'>;
   ensureDetail: (id: string) => Promise<Email | null>;
-  c: ThemePalette;
+  ensureThread: (threadId: string) => Promise<string[]>;
+  scheduleMarkRead: (email: Email) => () => void;
   styles: ReturnType<typeof makeStyles>;
   bottomBarHeight: number;
-  attachmentPosition: 'beside-sender' | 'below-header';
-  hideInlineImageAttachments: boolean;
-  downloadingBlobId: string | null;
   onToggleStar: (email: Email) => void;
-  onPressAttachment: (email: Email, blobId: string, name: string | undefined, type: string | undefined) => void;
+  onAddressPress: (address: EmailAddress) => void;
+  onEmailPatched: (email: Email) => void;
+  onReply: (mode: 'reply' | 'replyAll' | 'forward', email: Email) => void;
   onSwipe: (direction: 'prev' | 'next') => void;
   onZoomChange: (zoom: { pinching: boolean; zoomed: boolean }) => void;
 }
 
-// One swipeable page: the scrollable subject / sender / attachments / body for a
-// single message. The pager keeps three of these mounted (prev, current, next)
-// so a swipe slides ready content into view. Each pane owns its own vertical
-// scroll position and "show all attachments" toggle, and renders directly from
-// the email passed to it — neighbours show real content, not a placeholder.
+// One swipeable page: the subject plus either a single message or the whole
+// conversation as collapsible cards (newest + unread expanded, mark-read on
+// expand). The pager keeps three of these mounted (prev, current, next) so a
+// swipe slides ready content into view.
 function EmailPane({
-  id, email, jmapAccountId, ensureDetail, c, styles, bottomBarHeight, attachmentPosition,
-  hideInlineImageAttachments, downloadingBlobId, onToggleStar, onPressAttachment, onSwipe,
-  onZoomChange,
+  id, threadIdHint, email, detailCache, threadIds, threading, jmapAccountId, currentMailboxRole,
+  identities, themeOverrides, ensureDetail, ensureThread, scheduleMarkRead, styles, bottomBarHeight,
+  onToggleStar, onAddressPress, onEmailPatched, onReply, onSwipe, onZoomChange,
 }: EmailPaneProps) {
-  const [attachmentsExpanded, setAttachmentsExpanded] = React.useState(false);
+  const c = useColors();
+  const t = useLocaleStore((s) => s.t);
   // Freeze the pane's vertical scroll while a pinch is in flight so a two-
-  // finger zoom can't fling the page; while merely zoomed, vertical scrolling
-  // stays on — it is how the user pans the (taller) zoomed content vertically.
+  // finger zoom can't fling the page.
   const [pinching, setPinching] = React.useState(false);
+  // Which cards are open. Seeded once the conversation arrives: the opened
+  // message, the newest one and every unread one, like the webmail.
+  const [expanded, setExpanded] = React.useState<Set<string> | null>(null);
+  const readTimers = React.useRef(new Map<string, () => void>()).current;
 
-  // Each pane owns loading its own message: when the list mounts this page and
-  // its detail isn't cached yet, fetch it (coalesced upstream). The shared
-  // cache then re-renders the pane with real content.
   React.useEffect(() => {
     if (!email) void ensureDetail(id);
   }, [id, email, ensureDetail]);
 
-  // Detail not fetched yet. Show a skeleton of the pane layout instead of a
-  // spinner so the transition into real content doesn't jump.
+  const threadId = email?.threadId ?? threadIdHint;
+  React.useEffect(() => {
+    if (threading && threadId && !threadIds) void ensureThread(threadId);
+  }, [threading, threadId, threadIds, ensureThread]);
+
+  React.useEffect(() => {
+    if (!threadIds || expanded) return;
+    const seed = new Set<string>();
+    for (const mid of threadIds) {
+      const m = detailCache.get(mid);
+      if (m && !m.keywords?.$seen) seed.add(mid);
+    }
+    seed.add(id);
+    if (threadIds.length > 0) seed.add(threadIds[threadIds.length - 1]);
+    setExpanded(seed);
+  }, [threadIds, expanded, detailCache, id]);
+
+  React.useEffect(() => () => { readTimers.forEach((cancel) => cancel()); readTimers.clear(); }, [readTimers]);
+
+  const toggleCard = (mid: string) => {
+    setExpanded((prev) => {
+      const next = new Set(prev ?? []);
+      if (next.has(mid)) {
+        next.delete(mid);
+      } else {
+        next.add(mid);
+        const m = detailCache.get(mid);
+        if (m && mid !== id) {
+          readTimers.get(mid)?.();
+          readTimers.set(mid, scheduleMarkRead(m));
+        }
+      }
+      return next;
+    });
+  };
+
   if (!email) {
     return <EmailPaneSkeleton styles={styles} />;
   }
 
-  const from = email.from?.[0];
-  const starred = !!email.keywords?.$flagged;
-  const subject = email.subject || '(no subject)';
-
-  const renderAttachments = () => {
-    const all = email.attachments;
-    if (!all || all.length === 0) return null;
-    // hideInlineImageAttachments: drop chips for images already shown inline
-    // in the body (any image attachment with a cid:). Non-image inline
-    // attachments stay visible because the user wouldn't see them otherwise.
-    const atts = hideInlineImageAttachments
-      ? all.filter((att) => !(att.cid && (att.type ?? '').startsWith('image/')))
-      : all;
-    if (atts.length === 0) return null;
-    const visible = attachmentsExpanded ? atts : atts.slice(0, 3);
-    return (
-      <View style={styles.attachmentsBlock}>
-        <View style={styles.attachmentsRow}>
-          {visible.map((att, idx) => {
-            const isDownloading = downloadingBlobId === att.blobId;
-            return (
-              <Pressable
-                key={att.blobId ?? idx}
-                style={({ pressed }) => [
-                  styles.attachmentChip,
-                  pressed && styles.attachmentChipPressed,
-                ]}
-                onPress={() => onPressAttachment(email, att.blobId, att.name, att.type)}
-                disabled={!!downloadingBlobId}
-              >
-                {isDownloading ? (
-                  <ActivityIndicator size="small" color={c.textMuted} />
-                ) : (
-                  <Paperclip size={14} color={c.textMuted} />
-                )}
-                <Text style={styles.attachmentName} numberOfLines={1}>
-                  {att.name || 'attachment'}
-                </Text>
-                <Text style={styles.attachmentSize}>{formatSize(att.size)}</Text>
-                <Download size={14} color={c.textMuted} />
-              </Pressable>
-            );
-          })}
-        </View>
-        {atts.length > 3 && (
-          <Pressable
-            onPress={() => setAttachmentsExpanded((v) => !v)}
-            style={({ pressed }) => [
-              styles.attachmentsToggle,
-              pressed && styles.attachmentsTogglePressed,
-            ]}
-            hitSlop={6}
-          >
-            <Text style={styles.attachmentsToggleText}>
-              {attachmentsExpanded ? 'Show less' : `Show all (${atts.length})`}
-            </Text>
-          </Pressable>
-        )}
-      </View>
-    );
-  };
+  const subject = email.subject || t('email_viewer.no_subject', '(No Subject)');
+  const conversation = threading && threadIds && threadIds.length > 1
+    ? threadIds.map((mid) => detailCache.get(mid)).filter((m): m is Email => !!m)
+    : null;
+  const newest = conversation ? conversation[conversation.length - 1] : email;
 
   return (
     <ScrollView
@@ -818,63 +889,68 @@ function EmailPane({
       <View style={styles.subjectBlock}>
         <View style={styles.subjectRow}>
           <Text style={styles.subjectText}>{subject}</Text>
-          <Pressable onPress={() => onToggleStar(email)} hitSlop={8} style={styles.subjectStar}>
-            <Star
-              size={18}
-              color={starred ? c.starred : c.textMuted}
-              fill={starred ? c.starred : 'transparent'}
-            />
-          </Pressable>
+          {conversation ? (
+            <View style={styles.threadCount}>
+              <Text style={styles.threadCountText}>{conversation.length}</Text>
+            </View>
+          ) : (
+            <Pressable onPress={() => onToggleStar(email)} hitSlop={8} style={styles.subjectStar}>
+              <Star
+                size={18}
+                color={email.keywords?.$flagged ? c.starred : c.textMuted}
+                fill={email.keywords?.$flagged ? c.starred : 'transparent'}
+              />
+            </Pressable>
+          )}
         </View>
       </View>
 
-      {/* Sender info */}
-      <View style={styles.senderBlock}>
-        <View style={styles.senderRow}>
-          <SenderAvatar
-            name={from?.name}
-            email={from?.email}
-            size={componentSizes.avatarMd}
+      {threading && threadId && !threadIds && (
+        <View style={styles.threadLoading}>
+          <ActivityIndicator size="small" color={c.textMuted} />
+          <Text style={styles.threadLoadingText}>{t('threads.loading', 'Loading conversation...')}</Text>
+        </View>
+      )}
+
+      {conversation ? (
+        conversation.map((m) => (
+          <ThreadMessageCard
+            key={m.id}
+            email={m}
+            expanded={expanded?.has(m.id) ?? m.id === id}
+            onToggleExpanded={() => toggleCard(m.id)}
+            onReply={onReply}
+            jmapAccountId={jmapAccountId}
+            identities={identities}
+            currentMailboxRole={currentMailboxRole}
+            themeOverride={themeOverrides[m.id] ?? null}
+            onSwipe={onSwipe}
+            onZoomChange={(z) => { setPinching(z.pinching); onZoomChange(z); }}
+            onToggleStar={onToggleStar}
+            onAddressPress={onAddressPress}
+            onEmailPatched={onEmailPatched}
           />
-          <View style={styles.senderInfo}>
-            <Text style={styles.senderName} numberOfLines={1}>
-              {from?.name || from?.email || 'Unknown sender'}
-            </Text>
-            {from?.name && from?.email ? (
-              <Text style={styles.senderEmail} numberOfLines={1}>{from.email}</Text>
-            ) : null}
-            <Text style={styles.senderRecipients} numberOfLines={1}>
-              <Text style={styles.senderRecipientsLabel}>to </Text>
-              {email.to?.map((t) => t.name || t.email).join(', ') || '-'}
-            </Text>
-          </View>
-          <View style={styles.senderMeta}>
-            <Text style={styles.senderDate}>{formatHeaderDate(email.receivedAt)}</Text>
-            <Text style={styles.senderTime}>
-              {formatHeaderTime(email.receivedAt)}
-              {email.size > 0 ? ` · ${formatSize(email.size)}` : ''}
-            </Text>
-          </View>
-        </View>
-        {attachmentPosition === 'beside-sender' && renderAttachments()}
-      </View>
-
-      {/* Attachments chips (full-width below header) */}
-      {attachmentPosition === 'below-header' && renderAttachments()}
-
-      {/* Calendar invitation (auto-detected .ics) */}
-      <CalendarInvitationBanner email={email} jmapAccountId={jmapAccountId} />
-
-      {/* Body */}
-      <View style={styles.bodyBlock}>
-        <EmailBodyView
+        ))
+      ) : (
+        <MessageContent
           email={email}
-          senderEmail={from?.email}
           jmapAccountId={jmapAccountId}
+          identities={identities}
+          currentMailboxRole={currentMailboxRole}
+          themeOverride={themeOverrides[email.id] ?? null}
           onSwipe={onSwipe}
           onZoomChange={(z) => { setPinching(z.pinching); onZoomChange(z); }}
+          onAddressPress={onAddressPress}
+          onEmailPatched={onEmailPatched}
         />
-      </View>
+      )}
+
+      <QuickReplyBox
+        email={newest}
+        jmapAccountId={jmapAccountId}
+        onMoreOptions={() => onReply('reply', newest)}
+        onSent={onEmailPatched}
+      />
     </ScrollView>
   );
 }
@@ -902,18 +978,12 @@ function EmailPaneSkeleton({ styles }: { styles: ReturnType<typeof makeStyles> }
       <View style={styles.subjectBlock}>
         <View style={[styles.skeletonBone, { height: 20, width: '88%' }]} />
       </View>
-      <View style={styles.senderBlock}>
-        <View style={styles.senderRow}>
-          <View style={styles.skeletonAvatar} />
-          <View style={styles.senderInfo}>
-            <View style={[styles.skeletonBone, { height: 14, width: '55%' }]} />
-            <View style={[styles.skeletonBone, { height: 11, width: '70%', marginTop: 6 }]} />
-            <View style={[styles.skeletonBone, { height: 11, width: '45%', marginTop: 6 }]} />
-          </View>
-          <View style={styles.senderMeta}>
-            <View style={[styles.skeletonBone, { height: 11, width: 86 }]} />
-            <View style={[styles.skeletonBone, { height: 11, width: 64, marginTop: 6 }]} />
-          </View>
+      <View style={styles.skeletonSender}>
+        <View style={styles.skeletonAvatar} />
+        <View style={{ flex: 1 }}>
+          <View style={[styles.skeletonBone, { height: 14, width: '55%' }]} />
+          <View style={[styles.skeletonBone, { height: 11, width: '70%', marginTop: 6 }]} />
+          <View style={[styles.skeletonBone, { height: 11, width: '45%', marginTop: 6 }]} />
         </View>
       </View>
       <View style={styles.skeletonBody}>
@@ -937,26 +1007,33 @@ interface MoreMenuSheetProps {
   isInJunk: boolean;
   canViewSource: boolean;
   canExport: boolean;
+  renderDark: boolean;
+  hasSender: boolean;
   onArchive: () => void;
   onToggleUnread: () => void;
   onMove: () => void;
   onTag: () => void;
   onToggleSpam: () => void;
+  onToggleTheme: () => void;
+  onSenderActions: () => void;
+  onForwardAsAttachment: () => void;
   onViewSource: () => void;
   onExport: () => void;
 }
 
 function MoreMenuSheet({
   visible, onClose, unread, canArchive, canMarkUnread, canMove, canTag,
-  showSpam, isInJunk, canViewSource, canExport,
-  onArchive, onToggleUnread, onMove, onTag, onToggleSpam, onViewSource, onExport,
+  showSpam, isInJunk, canViewSource, canExport, renderDark, hasSender,
+  onArchive, onToggleUnread, onMove, onTag, onToggleSpam, onToggleTheme, onSenderActions,
+  onForwardAsAttachment, onViewSource, onExport,
 }: MoreMenuSheetProps) {
   const c = useColors();
   const styles = React.useMemo(() => makeStyles(c), [c]);
+  const t = useLocaleStore((s) => s.t);
   const insets = useSafeAreaInsets();
-  const slideY = React.useRef(new Animated.Value(400)).current;
+  const slideY = React.useRef(new Animated.Value(600)).current;
   const overlayOpacity = React.useRef(new Animated.Value(0)).current;
-  const dragHandlers = useSheetDrag({ slideY, closedY: 400, onClose });
+  const dragHandlers = useSheetDrag({ slideY, closedY: 600, onClose });
 
   React.useEffect(() => {
     if (visible) {
@@ -966,7 +1043,7 @@ function MoreMenuSheet({
       ]).start();
     } else {
       Animated.parallel([
-        Animated.timing(slideY, { toValue: 400, duration: 180, easing: Easing.in(Easing.cubic), useNativeDriver: true }),
+        Animated.timing(slideY, { toValue: 600, duration: 180, easing: Easing.in(Easing.cubic), useNativeDriver: true }),
         Animated.timing(overlayOpacity, { toValue: 0, duration: 180, useNativeDriver: true }),
       ]).start();
     }
@@ -988,75 +1065,97 @@ function MoreMenuSheet({
             <View style={styles.sheetHandle} />
           </View>
           <View style={styles.sheetHeader}>
-            <Text style={styles.sheetTitle}>More actions</Text>
+            <Text style={styles.sheetTitle}>{t('email_viewer.more_actions', 'More actions')}</Text>
             <Pressable onPress={onClose} hitSlop={8} style={styles.sheetClose}>
               <X size={18} color={c.textSecondary} />
             </Pressable>
           </View>
         </View>
-        {canArchive && (
+        <ScrollView style={styles.sheetScroll} bounces={false}>
+          {canArchive && (
+            <MoreMenuItem
+              icon={<Archive size={18} color={c.textSecondary} />}
+              label={t('email_viewer.archive', 'Archive')}
+              onPress={onArchive}
+            />
+          )}
+          {canMarkUnread && (
+            <MoreMenuItem
+              icon={
+                unread ? (
+                  <MailOpen size={18} color={c.textSecondary} />
+                ) : (
+                  <Mail size={18} color={c.textSecondary} />
+                )
+              }
+              label={unread ? t('email_viewer.mark_read', 'Mark as read') : t('email_viewer.mark_unread', 'Mark as unread')}
+              onPress={onToggleUnread}
+            />
+          )}
+          {canMove && (
+            <MoreMenuItem
+              icon={<FolderInput size={18} color={c.textSecondary} />}
+              label={t('email_viewer.move_to', 'Move to...')}
+              onPress={onMove}
+              trailing={<ChevronRight size={16} color={c.textMuted} />}
+            />
+          )}
+          {canTag && (
+            <MoreMenuItem
+              icon={<Tag size={18} color={c.textSecondary} />}
+              label={t('email_viewer.set_tag', 'Set tag')}
+              onPress={onTag}
+              trailing={<ChevronRight size={16} color={c.textMuted} />}
+            />
+          )}
+          {showSpam && (
+            <MoreMenuItem
+              icon={
+                isInJunk ? (
+                  <ShieldCheck size={18} color={c.success} />
+                ) : (
+                  <ShieldAlert size={18} color={c.error} />
+                )
+              }
+              label={isInJunk ? t('email_viewer.not_spam_short', 'Not spam') : t('email_viewer.spam.button_title', 'Report spam')}
+              onPress={onToggleSpam}
+            />
+          )}
           <MoreMenuItem
-            icon={<Archive size={18} color={c.textSecondary} />}
-            label="Archive"
-            onPress={onArchive}
+            icon={renderDark ? <Sun size={18} color={c.textSecondary} /> : <Moon size={18} color={c.textSecondary} />}
+            label={renderDark ? t('email_viewer.view_light_mode', 'View in light mode') : t('email_viewer.view_dark_mode', 'View in dark mode')}
+            onPress={onToggleTheme}
           />
-        )}
-        {canMarkUnread && (
-          <MoreMenuItem
-            icon={
-              unread ? (
-                <MailOpen size={18} color={c.textSecondary} />
-              ) : (
-                <Mail size={18} color={c.textSecondary} />
-              )
-            }
-            label={unread ? 'Mark as read' : 'Mark as unread'}
-            onPress={onToggleUnread}
-          />
-        )}
-        {canMove && (
-          <MoreMenuItem
-            icon={<FolderInput size={18} color={c.textSecondary} />}
-            label="Move to folder…"
-            onPress={onMove}
-            trailing={<ChevronRight size={16} color={c.textMuted} />}
-          />
-        )}
-        {canTag && (
-          <MoreMenuItem
-            icon={<Tag size={18} color={c.textSecondary} />}
-            label="Tag…"
-            onPress={onTag}
-            trailing={<ChevronRight size={16} color={c.textMuted} />}
-          />
-        )}
-        {showSpam && (
-          <MoreMenuItem
-            icon={
-              isInJunk ? (
-                <ShieldCheck size={18} color={c.success} />
-              ) : (
-                <ShieldAlert size={18} color={c.error} />
-              )
-            }
-            label={isInJunk ? 'Not spam' : 'Mark as spam'}
-            onPress={onToggleSpam}
-          />
-        )}
-        {canViewSource && (
-          <MoreMenuItem
-            icon={<Code size={18} color={c.textSecondary} />}
-            label="View source"
-            onPress={onViewSource}
-          />
-        )}
-        {canExport && (
-          <MoreMenuItem
-            icon={<Download size={18} color={c.textSecondary} />}
-            label="Export email (.eml)"
-            onPress={onExport}
-          />
-        )}
+          {hasSender && (
+            <MoreMenuItem
+              icon={<UserRoundPlus size={18} color={c.textSecondary} />}
+              label={t('email_viewer.sender_actions', 'Sender…')}
+              onPress={onSenderActions}
+              trailing={<ChevronRight size={16} color={c.textMuted} />}
+            />
+          )}
+          {canExport && (
+            <MoreMenuItem
+              icon={<FileInput size={18} color={c.textSecondary} />}
+              label={t('email_viewer.forward_as_attachment', 'Forward as attachment')}
+              onPress={onForwardAsAttachment}
+            />
+          )}
+          {canViewSource && (
+            <MoreMenuItem
+              icon={<Code size={18} color={c.textSecondary} />}
+              label={t('email_viewer.view_source', 'View source')}
+              onPress={onViewSource}
+            />
+          )}
+          {canExport && (
+            <MoreMenuItem
+              icon={<Download size={18} color={c.textSecondary} />}
+              label={t('email_viewer.export_email', 'Export as .eml')}
+              onPress={onExport}
+            />
+          )}
+        </ScrollView>
       </Animated.View>
     </Modal>
   );
@@ -1073,6 +1172,7 @@ interface TagMenuSheetProps {
 function TagMenuSheet({ visible, onClose, keywords, activeKeywords, onToggle }: TagMenuSheetProps) {
   const c = useColors();
   const styles = React.useMemo(() => makeStyles(c), [c]);
+  const t = useLocaleStore((s) => s.t);
   const insets = useSafeAreaInsets();
   const slideY = React.useRef(new Animated.Value(500)).current;
   const overlayOpacity = React.useRef(new Animated.Value(0)).current;
@@ -1108,7 +1208,7 @@ function TagMenuSheet({ visible, onClose, keywords, activeKeywords, onToggle }:
             <View style={styles.sheetHandle} />
           </View>
           <View style={styles.sheetHeader}>
-            <Text style={styles.sheetTitle}>Tags</Text>
+            <Text style={styles.sheetTitle}>{t('email_viewer.tag', 'Tag')}</Text>
             <Pressable onPress={onClose} hitSlop={8} style={styles.sheetClose}>
               <X size={18} color={c.textSecondary} />
             </Pressable>
@@ -1116,7 +1216,7 @@ function TagMenuSheet({ visible, onClose, keywords, activeKeywords, onToggle }:
         </View>
         {keywords.length === 0 ? (
           <Text style={{ ...typography.body, color: c.textMuted, paddingVertical: spacing.lg, paddingHorizontal: spacing.lg }}>
-            No tags yet. Add some in Settings → Keywords & Labels.
+            {t('email_viewer.tag_no_matches', 'No matching tags')}
           </Text>
         ) : (
           keywords.map((kw) => {
@@ -1246,7 +1346,6 @@ function makeStyles(c: ThemePalette) {
     padding: spacing.lg,
   },
   errorText: { ...typography.body, color: c.error, textAlign: 'center' },
-  // Pager: the horizontal page-snapping list fills the area between the bars.
   pagerViewport: { flex: 1, backgroundColor: c.background },
   scroll: { flex: 1, backgroundColor: c.background },
 
@@ -1274,114 +1373,39 @@ function makeStyles(c: ThemePalette) {
     color: c.text,
     letterSpacing: -0.2,
   },
-
-  // Sender block
-  senderBlock: {
-    backgroundColor: c.background,
-    borderBottomWidth: 1,
-    borderBottomColor: c.border,
-    paddingHorizontal: spacing.lg,
-    paddingVertical: spacing.md,
+  threadCount: {
+    minWidth: 24,
+    height: 24,
+    borderRadius: 12,
+    paddingHorizontal: 6,
+    backgroundColor: c.surfaceHover,
+    alignItems: 'center',
+    justifyContent: 'center',
+    marginTop: 2,
   },
-  senderRow: {
+  threadCountText: { ...typography.small, color: c.textSecondary, fontWeight: '600' },
+  threadLoading: {
     flexDirection: 'row',
-    alignItems: 'flex-start',
-    gap: spacing.md,
-  },
-  senderInfo: { flex: 1, minWidth: 0 },
-  senderName: {
-    ...typography.bodySemibold,
-    color: c.text,
-  },
-  senderEmail: {
-    ...typography.caption,
-    color: c.textSecondary,
-    marginTop: 2,
-  },
-  senderRecipients: {
-    ...typography.caption,
-    color: c.textSecondary,
-    marginTop: 4,
-  },
-  senderRecipientsLabel: {
-    color: c.textMuted,
-  },
-  senderMeta: {
-    alignItems: 'flex-end',
-    paddingTop: 1,
-  },
-  senderDate: {
-    ...typography.caption,
-    color: c.textSecondary,
-  },
-  senderTime: {
-    ...typography.caption,
-    color: c.textMuted,
-    marginTop: 2,
-  },
-
-  // Attachments
-  attachmentsBlock: {
-    backgroundColor: c.background,
-    borderBottomWidth: 1,
-    borderBottomColor: c.border,
+    alignItems: 'center',
+    gap: spacing.sm,
     paddingHorizontal: spacing.lg,
     paddingVertical: spacing.sm,
   },
-  attachmentsRow: {
-    flexDirection: 'row',
-    flexWrap: 'wrap',
-    gap: spacing.xs,
-  },
-  attachmentChip: {
-    flexDirection: 'row',
-    alignItems: 'center',
-    gap: spacing.xs,
-    paddingHorizontal: spacing.sm,
-    paddingVertical: 6,
-    backgroundColor: c.surface,
-    borderWidth: 1,
-    borderColor: c.border,
-    borderRadius: radius.sm,
-  },
-  attachmentChipPressed: {
-    backgroundColor: c.surfaceHover,
-    opacity: 0.85,
-  },
-  attachmentName: {
-    ...typography.caption,
-    color: c.text,
-    maxWidth: 180,
-  },
-  attachmentSize: {
-    ...typography.small,
-    color: c.textMuted,
-  },
-  attachmentsToggle: {
-    marginTop: spacing.xs,
-    alignSelf: 'flex-start',
-    paddingVertical: 4,
-    paddingHorizontal: spacing.xs,
-  },
-  attachmentsTogglePressed: {
-    opacity: 0.6,
-  },
-  attachmentsToggleText: {
-    ...typography.caption,
-    color: c.primary,
-    fontWeight: '600',
-  },
-
-  // Body
-  bodyBlock: {
-    backgroundColor: c.background,
-  },
+  threadLoadingText: { ...typography.caption, color: c.textMuted },
 
   // Loading skeleton
   skeletonBone: {
     backgroundColor: c.surfaceHover,
     borderRadius: radius.xs,
   },
+  skeletonSender: {
+    flexDirection: 'row',
+    gap: spacing.md,
+    paddingHorizontal: spacing.lg,
+    paddingVertical: spacing.md,
+    borderBottomWidth: 1,
+    borderBottomColor: c.border,
+  },
   skeletonAvatar: {
     width: componentSizes.avatarMd,
     height: componentSizes.avatarMd,
@@ -1425,7 +1449,7 @@ function makeStyles(c: ThemePalette) {
     color: c.textMuted,
   },
 
-  // Bottom sheet (More menu / Move folder picker)
+  // Bottom sheet (More menu / Tag picker)
   sheetOverlay: {
     ...StyleSheet.absoluteFillObject,
     backgroundColor: 'rgba(0,0,0,0.5)',
@@ -1436,6 +1460,7 @@ function makeStyles(c: ThemePalette) {
     left: 0,
     right: 0,
     bottom: 0,
+    maxHeight: '85%',
     backgroundColor: c.popover,
     borderTopLeftRadius: radius.lg,
     borderTopRightRadius: radius.lg,
@@ -1443,6 +1468,7 @@ function makeStyles(c: ThemePalette) {
     borderColor: c.border,
     paddingTop: spacing.sm,
   },
+  sheetScroll: { flexGrow: 0 },
   sheetHandleHit: {
     alignItems: 'center',
     paddingTop: spacing.xs,