diff --git a/mobile/src/session/mobile-session-route-parity.test.ts b/mobile/src/session/mobile-session-route-parity.test.ts
index 76435561664..7d0c5c6de46 100644
--- a/mobile/src/session/mobile-session-route-parity.test.ts
+++ b/mobile/src/session/mobile-session-route-parity.test.ts
@@ -62,11 +62,11 @@ const HOST_COMPONENT_NAMES = new Set([
   'View'
 ])
 
-const HEAD_MAIN_HOOK_SHA256 = 'c3e33699e3e3fa7e24408f3d4946fcc451e9b9419442d985c4ccde01782e5114'
-const HEAD_HOOK_BINDING_SHA256 = '7f907e028893721d662eeee0aa9002ad1e00359948f39fb148d274596cd9b3c0'
+const HEAD_MAIN_HOOK_SHA256 = '11cd92aec686a6e47b23114ec31da86152a850b064821578b165fabfbce53b27'
+const HEAD_HOOK_BINDING_SHA256 = 'f8bce7101a26b4d794bb58dee54702424a4965cc81dec5c758ca56cd5a6f4ce8'
 const HEAD_CALLBACK_IDENTITY_SHA256 =
   '2a9e4825df007f6ef53b81aa5004991d6318eee7507b44d625c07e630be432eb'
-const HEAD_CALLBACK_BODY_SHA256 = 'af7f3c62954250d4be7ee432ecd10dc2689792aad8230fed2d1d68bbc892d776'
+const HEAD_CALLBACK_BODY_SHA256 = '85c4f4605e66c45e2b6bc7de739cb3493d9e2d0db9c9242c379db8ed34a8cefe'
 const HEAD_EFFECT_SHA256 = 'd9ebfaabc1e79773cdada7ab370b20459ed972f1f8edce1652199f4d0391cd13'
 const HEAD_CONTENT_HOOK_SHA256 = '9c3b612fef3f370d66873aefdbe1d701f20cb64ded31fef5cc45fde6f8189581'
 const HEAD_NESTED_FUNCTION_SHA256 =
@@ -472,7 +472,7 @@ describe('mobile session route extraction parity', () => {
     const contentBindings = CONTENT_COMPONENT_NAMES.flatMap(
       (name) => readHookFacts(name, definitions).bindings
     )
-    expect(main.hooks).toHaveLength(267)
+    expect(main.hooks).toHaveLength(268)
     expect(hash(main.hooks)).toBe(HEAD_MAIN_HOOK_SHA256)
     expect(hash(main.bindings)).toBe(HEAD_HOOK_BINDING_SHA256)
     expect(main.callbacks).toHaveLength(77)
diff --git a/mobile/src/session/use-mobile-session-accessory-selection.ts b/mobile/src/session/use-mobile-session-accessory-selection.ts
index 356bf11952d..ad0116cb9c6 100644
--- a/mobile/src/session/use-mobile-session-accessory-selection.ts
+++ b/mobile/src/session/use-mobile-session-accessory-selection.ts
@@ -14,6 +14,8 @@ import type {
 } from '../terminal/terminal-webview-contract'
 import type { createTerminalLiveAccessoryInput } from '../terminal/terminal-live-accessory-input'
 import { clearTerminalLiveInputFocusTimer } from '../terminal/terminal-live-input'
+import { stripTerminalSelectionGutter } from '../../../src/shared/terminal-selection-gutter'
+import { useTerminalCopyTrimsGutter } from '../terminal/terminal-copy-gutter-preference'
 import { getRepoIdFromMobileWorktreeId } from './mobile-session-route-helpers'
 import type { RuntimeRepoSummary } from './mobile-session-route-types'
 import type { MobileSessionTerminalInputModel } from './use-mobile-session-terminal-input'
@@ -23,6 +25,7 @@ export function useMobileSessionAccessorySelection(scope: MobileSessionTerminalI
     worktreeId,
     isFloatingWorkspaceRoute,
     client,
+    connState,
     setTerminalKeyboardMetrics,
     setSelectModeActive,
     setCanPaste,
@@ -41,6 +44,7 @@ export function useMobileSessionAccessorySelection(scope: MobileSessionTerminalI
     handleAccessoryKey,
     clearSessionTabActionSheetKeyboardListener
   } = scope
+  const trimsGutterRef = useTerminalCopyTrimsGutter(client, connState)
   // Why: hold-to-repeat matches iOS cadence (400ms then 45ms); non-repeatable keys fire once (holding is destructive).
   const repeatTimeoutRef = useRef<ReturnType<typeof setTimeout> | null>(null)
   const repeatIntervalRef = useRef<ReturnType<typeof setInterval> | null>(null)
@@ -115,7 +119,9 @@ export function useMobileSessionAccessorySelection(scope: MobileSessionTerminalI
         return
       }
       try {
-        await Clipboard.setStringAsync(text)
+        await Clipboard.setStringAsync(
+          trimsGutterRef.current ? stripTerminalSelectionGutter(text) : text
+        )
         triggerSuccess()
         // Why: Android 13+ shows its own system copy toast; iOS shows none, so only iOS needs our in-app toast.
         if (Platform.OS === 'ios') {
diff --git a/mobile/src/terminal/terminal-copy-gutter-preference.ts b/mobile/src/terminal/terminal-copy-gutter-preference.ts
new file mode 100644
index 00000000000..b5e80d542d3
--- /dev/null
+++ b/mobile/src/terminal/terminal-copy-gutter-preference.ts
@@ -0,0 +1,43 @@
+import { useEffect, useRef, type RefObject } from 'react'
+import { terminalCopyTrimsGutterRead } from '../transport/settings-read-operations'
+import type { RpcClient } from '../transport/rpc-client'
+import type { ConnectionState } from '../transport/types'
+
+/**
+ * Desktop owns "Trim Gutter on Copy" (GlobalSettings.terminalCopyTrimsGutter);
+ * mobile mirrors it so turning the setting off yields verbatim screen cells on
+ * every surface. Read once per connection — the mobile RPC has no
+ * settings-change stream — and default to on while the read is in flight.
+ */
+export function useTerminalCopyTrimsGutter(
+  client: RpcClient | null,
+  connState: ConnectionState
+): RefObject<boolean> {
+  const trimsGutterRef = useRef(true)
+
+  useEffect(() => {
+    if (!client || connState !== 'connected') {
+      return
+    }
+    let stale = false
+    void terminalCopyTrimsGutterRead
+      .request(client)
+      .then((response) => {
+        if (stale) {
+          return
+        }
+        const preference = terminalCopyTrimsGutterRead.interpret(response)
+        if (preference.accepted) {
+          trimsGutterRef.current = preference.value
+        }
+      })
+      .catch(() => {
+        // Best-effort: an unreachable host leaves the on-by-default trim in place.
+      })
+    return () => {
+      stale = true
+    }
+  }, [client, connState])
+
+  return trimsGutterRef
+}
diff --git a/mobile/src/transport/settings-read-operations.test.ts b/mobile/src/transport/settings-read-operations.test.ts
index 3a81da9942f..07f4ff771d4 100644
--- a/mobile/src/transport/settings-read-operations.test.ts
+++ b/mobile/src/transport/settings-read-operations.test.ts
@@ -8,7 +8,8 @@ import {
   settingsRead,
   optionalSettingsRead,
   botOverridesRead,
-  newTabSettingsRead
+  newTabSettingsRead,
+  terminalCopyTrimsGutterRead
 } from './settings-read-operations'
 import type { RpcResponse } from './types'
 
@@ -91,6 +92,24 @@ describe('settings historical acceptance', () => {
     expect(botOverridesRead.interpret(empty)).toEqual({ accepted: true, value: [] })
   })
 
+  it('reads the gutter-trim preference, treating an older host as opted in', async () => {
+    const off = await terminalCopyTrimsGutterRead.request(
+      replyWith(success({ settings: { terminalCopyTrimsGutter: false } }))
+    )
+    expect(terminalCopyTrimsGutterRead.interpret(off)).toEqual({ accepted: true, value: false })
+    const on = await terminalCopyTrimsGutterRead.request(
+      replyWith(success({ settings: { terminalCopyTrimsGutter: true } }))
+    )
+    expect(terminalCopyTrimsGutterRead.interpret(on)).toEqual({ accepted: true, value: true })
+    // A host predating the setting sends no key; the desktop default is on.
+    const absent = await terminalCopyTrimsGutterRead.request(replyWith(success({ settings: {} })))
+    expect(terminalCopyTrimsGutterRead.interpret(absent)).toEqual({ accepted: true, value: true })
+    const empty = await terminalCopyTrimsGutterRead.request(replyWith(success(null)))
+    expect(terminalCopyTrimsGutterRead.interpret(empty)).toEqual({ accepted: true, value: true })
+    const refused = await terminalCopyTrimsGutterRead.request(replyWith(refusal()))
+    expect(terminalCopyTrimsGutterRead.interpret(refused)).toEqual({ accepted: false })
+  })
+
   it('does not read a stale payload until its caller permits interpretation', async () => {
     const read = vi.fn(() => ({}))
     const reply = await settingsRead.request(
diff --git a/mobile/src/transport/settings-read-operations.ts b/mobile/src/transport/settings-read-operations.ts
index f33471dcaf2..c98c87798b3 100644
--- a/mobile/src/transport/settings-read-operations.ts
+++ b/mobile/src/transport/settings-read-operations.ts
@@ -82,6 +82,30 @@ export const newTabSettingsRead = bindDeferredRpcOperation(
   })
 )
 
+const copyTrimsGutterReader: RpcCompatibleReader<unknown, 'copy-trims-gutter', boolean> = (raw) => {
+  const settings = raw == null ? undefined : settingsMember(raw)
+  const trims: unknown =
+    settings == null ? undefined : Reflect.get(Object(settings), 'terminalCopyTrimsGutter')
+  return {
+    compatible: true,
+    variant: 'copy-trims-gutter',
+    // Why `!== false`: a host predating the setting sends no key, and the
+    // desktop default is on, so absence must read as on.
+    value: trims !== false,
+    salvage: { droppedPaths: [], droppedCount: 0 }
+  }
+}
+
+export const terminalCopyTrimsGutterRead = bindDeferredRpcOperation(
+  defineRpcOperation({
+    name: 'settings.terminal-copy-trims-gutter-or-skip',
+    method: 'settings.get',
+    acceptance: 'success-result-or-skip',
+    barrier: 'after-caller-barrier',
+    read: copyTrimsGutterReader
+  })
+)
+
 export const botOverridesRead = bindDeferredRpcOperation(
   defineRpcOperation({
     name: 'settings.bot-logins-or-skip',
diff --git a/src/main/runtime/runtime-client-settings-terminal-copy-projection.test.ts b/src/main/runtime/runtime-client-settings-terminal-copy-projection.test.ts
new file mode 100644
index 00000000000..8a6fad5065c
--- /dev/null
+++ b/src/main/runtime/runtime-client-settings-terminal-copy-projection.test.ts
@@ -0,0 +1,37 @@
+import { describe, expect, it } from 'vitest'
+import { RuntimeClientSettingsController } from './runtime-client-settings'
+import { createGlobalSettingsFixture } from '../../shared/global-settings-test-fixture'
+import type { GlobalSettings } from '../../shared/global-settings-types'
+
+// Why: `settings.get` is an explicit allowlist, not the whole settings object.
+// Mobile's terminal Copy reads terminalCopyTrimsGutter from it (#19770), and a
+// field missing here is indistinguishable on the client from an older host —
+// so the opt-out would silently never arrive.
+function projectionOf(settings: Partial<GlobalSettings>) {
+  // oxlint-disable-next-line typescript/consistent-type-assertions -- SAFETY: get() reads nothing but store.getSettings(); every other RuntimeStore member is unreachable from that path.
+  return new RuntimeClientSettingsController({ getSettings: () => settings } as never).get()
+}
+
+function hostSettings(overrides: Partial<GlobalSettings>): Partial<GlobalSettings> {
+  return { ...createGlobalSettingsFixture({ workspaceDir: '/w' }), ...overrides }
+}
+
+describe('RuntimeClientSettingsController terminal copy projection', () => {
+  it('publishes the gutter-trim opt-out to paired clients', () => {
+    expect(
+      projectionOf(hostSettings({ terminalCopyTrimsGutter: false })).terminalCopyTrimsGutter
+    ).toBe(false)
+  })
+
+  it('publishes the gutter-trim opt-in to paired clients', () => {
+    expect(
+      projectionOf(hostSettings({ terminalCopyTrimsGutter: true })).terminalCopyTrimsGutter
+    ).toBe(true)
+  })
+
+  it('reports on when the host has no persisted preference', () => {
+    const settings = hostSettings({})
+    delete settings.terminalCopyTrimsGutter
+    expect(projectionOf(settings).terminalCopyTrimsGutter).toBe(true)
+  })
+})
diff --git a/src/main/runtime/runtime-client-settings.ts b/src/main/runtime/runtime-client-settings.ts
index 900900700f3..4e36ee22024 100644
--- a/src/main/runtime/runtime-client-settings.ts
+++ b/src/main/runtime/runtime-client-settings.ts
@@ -27,6 +27,7 @@ export type RuntimeClientSettings = Pick<
   | 'agentDefaultArgs'
   | 'agentDefaultEnv'
   | 'agentStatusHooksEnabled'
+  | 'terminalCopyTrimsGutter'
   | 'defaultTaskSource'
   | 'defaultTaskViewPreset'
   | 'visibleTaskProviders'
@@ -97,6 +98,9 @@ export class RuntimeClientSettingsController {
       agentDefaultArgs: settings.agentDefaultArgs ?? {},
       agentDefaultEnv: settings.agentDefaultEnv ?? {},
       agentStatusHooksEnabled: settings.agentStatusHooksEnabled !== false,
+      // Why projected: mobile's terminal Copy honours this, and a host predating
+      // the setting sends no key, which the client reads as on (#19770).
+      terminalCopyTrimsGutter: settings.terminalCopyTrimsGutter !== false,
       defaultTaskSource: settings.defaultTaskSource ?? 'github',
       defaultTaskViewPreset: settings.defaultTaskViewPreset ?? 'issues',
       visibleTaskProviders: settings.visibleTaskProviders ?? [...TASK_PROVIDERS],
diff --git a/src/main/runtime/runtime-store-contract.ts b/src/main/runtime/runtime-store-contract.ts
index f3f5d5a8f51..b1471ff8efe 100644
--- a/src/main/runtime/runtime-store-contract.ts
+++ b/src/main/runtime/runtime-store-contract.ts
@@ -87,6 +87,7 @@ export type RuntimeStore = {
     terminalWindowsShell?: GlobalSettings['terminalWindowsShell']
     floatingTerminalEnabled?: GlobalSettings['floatingTerminalEnabled']
     agentStatusHooksEnabled?: GlobalSettings['agentStatusHooksEnabled']
+    terminalCopyTrimsGutter?: GlobalSettings['terminalCopyTrimsGutter']
     experimentalNativeChat?: GlobalSettings['experimentalNativeChat']
     openAgentTabsInChatByDefault?: GlobalSettings['openAgentTabsInChatByDefault']
     experimentalStructuredNativeChat?: GlobalSettings['experimentalStructuredNativeChat']
diff --git a/src/renderer/src/components/dashboard-popout/AgentTerminalPreview.tsx b/src/renderer/src/components/dashboard-popout/AgentTerminalPreview.tsx
index ec05a7105a5..f0360d2b795 100644
--- a/src/renderer/src/components/dashboard-popout/AgentTerminalPreview.tsx
+++ b/src/renderer/src/components/dashboard-popout/AgentTerminalPreview.tsx
@@ -26,6 +26,7 @@ import { createPreviewGridClaim } from './preview-grid-claim'
 import { createPreviewBoxFit } from './preview-terminal-box-fit'
 import { installPreviewTerminalAppMenuClipboard } from './preview-terminal-app-menu-clipboard'
 import { installPreviewTerminalRightClickPaste } from './preview-terminal-right-click-paste'
+import { installTerminalNativeCopyGutterTrim } from '@/components/terminal-pane/terminal-native-copy-gutter'
 import { isWindowsUserAgent } from '@/components/terminal-pane/pane-helpers'
 import type { TerminalPreviewDataPayload } from '../../../../shared/terminal-preview'
 
@@ -107,6 +108,7 @@ export function AgentTerminalPreview({
     let userInputDisposable: { dispose: () => void } | null = null
     let imeBridge: PreviewImeBridge | null = null
     let disposeKeyHandler: (() => void) | null = null
+    let disposeNativeCopyGutterTrim: (() => void) | null = null
     let disposeTerminalCompatibility: (() => void) | null = null
     // Why: mirrors the pane's tracker — the policy needs the flags the TUI
     // negotiated, and this preview parses the same output stream the pane does.
@@ -215,6 +217,13 @@ export function AgentTerminalPreview({
       })
     }
 
+    const installNativeCopyGutterTrim = (): void => {
+      if (!terminal) {
+        return
+      }
+      disposeNativeCopyGutterTrim = installTerminalNativeCopyGutterTrim(terminal).dispose
+    }
+
     const installTerminalCompatibility = (): void => {
       if (!terminal) {
         return
@@ -273,6 +282,7 @@ export function AgentTerminalPreview({
         }
         terminalRef.current = terminal
         installTerminalCompatibility()
+        installNativeCopyGutterTrim()
         installInputRouting()
         installImeNativeTextBridge()
         installKeyHandler()
@@ -340,6 +350,8 @@ export function AgentTerminalPreview({
         disposeTerminalCompatibility = null
         disposeKeyHandler?.()
         disposeKeyHandler = null
+        disposeNativeCopyGutterTrim?.()
+        disposeNativeCopyGutterTrim = null
         terminal?.dispose()
         terminal = null
         terminalRef.current = null
@@ -395,6 +407,7 @@ export function AgentTerminalPreview({
       disposeImeNativeTextBridge()
       disposeTerminalCompatibility?.()
       disposeKeyHandler?.()
+      disposeNativeCopyGutterTrim?.()
       void window.api.terminalPreview.unsubscribe(ptyId)
       terminal?.dispose()
       terminalRef.current = null
diff --git a/src/renderer/src/components/dashboard-popout/preview-terminal-key-handler.ts b/src/renderer/src/components/dashboard-popout/preview-terminal-key-handler.ts
index 29a6b80688d..1b263144a53 100644
--- a/src/renderer/src/components/dashboard-popout/preview-terminal-key-handler.ts
+++ b/src/renderer/src/components/dashboard-popout/preview-terminal-key-handler.ts
@@ -13,6 +13,7 @@ import {
   resolvePreviewShortcutAction,
   type PreviewShortcutContext
 } from './preview-terminal-shortcuts'
+import { readTerminalClipboardSelection } from '@/components/terminal-pane/terminal-clipboard-selection-text'
 
 /**
  * Installs the preview terminal's ONE custom key handler (xterm allows a single
@@ -109,7 +110,7 @@ export function installPreviewTerminalKeyHandler(args: {
     nativeOnlyShortcutTracker.prepareKeyDown(event)
     const keybindings = useAppStore.getState().keybindings
     if (keybindingMatchesAction('terminal.copySelection', event, platform, keybindings)) {
-      const selection = terminal.getSelection()
+      const selection = readTerminalClipboardSelection(terminal)
       if (
         !selection &&
         platform !== 'darwin' &&
diff --git a/src/renderer/src/components/settings/TerminalInteractionSection.tsx b/src/renderer/src/components/settings/TerminalInteractionSection.tsx
index f7c92e998a4..fb174a12a0a 100644
--- a/src/renderer/src/components/settings/TerminalInteractionSection.tsx
+++ b/src/renderer/src/components/settings/TerminalInteractionSection.tsx
@@ -1,8 +1,8 @@
 import type { GlobalSettings } from '../../../../shared/global-settings-types'
 import { RotateCcw } from 'lucide-react'
-import { Slider } from '../ui/slider'
 import { Button } from '../ui/button'
 import { Label } from '../ui/label'
+import { ScrollSpeedSlider } from './TerminalScrollSpeedSlider'
 import { SettingsSubsectionHeader, SettingsSwitchRow } from './SettingsFormControls'
 import { SearchableSetting } from './SearchableSetting'
 import { matchesSettingsSearch } from './settings-search'
@@ -27,65 +27,6 @@ type TerminalInteractionSectionProps = {
   searchQuery: string
 }
 
-type ScrollSpeedSliderProps = {
-  label: string
-  description: string
-  value: number
-  min: number
-  max: number
-  step: number
-  suffix: string
-  onChange: (value: number) => void
-}
-
-function formatScrollSpeedValue(value: number): string {
-  return Number.isInteger(value)
-    ? String(value)
-    : value.toFixed(2).replace(/0+$/, '').replace(/\.$/, '')
-}
-
-function ScrollSpeedSlider({
-  label,
-  description,
-  value,
-  min,
-  max,
-  step,
-  suffix,
-  onChange
-}: ScrollSpeedSliderProps): React.JSX.Element {
-  return (
-    <div className="rounded-md border border-border/60 bg-background/50 p-3">
-      <div className="flex items-start justify-between gap-3">
-        <div className="min-w-0 space-y-0.5">
-          <Label className="text-xs font-medium">{label}</Label>
-          <p className="text-[11px] leading-4 text-muted-foreground">{description}</p>
-        </div>
-        <span className="shrink-0 rounded-md border border-border/50 bg-muted/40 px-1.5 py-0.5 font-mono text-[11px] tabular-nums text-foreground">
-          {formatScrollSpeedValue(value)}
-          {suffix}
-        </span>
-      </div>
-      <Slider
-        className="mt-3"
-        min={min}
-        max={max}
-        step={step}
-        value={[value]}
-        onValueChange={([next]) => {
-          if (next !== undefined) {
-            onChange(next)
-          }
-        }}
-      />
-      <div className="mt-1 flex justify-between font-mono text-[10px] text-muted-foreground">
-        <span>{formatScrollSpeedValue(min)}</span>
-        <span>{formatScrollSpeedValue(max)}</span>
-      </div>
-    </div>
-  )
-}
-
 export function TerminalInteractionSection({
   settings,
   updateSettings,
@@ -332,6 +273,46 @@ export function TerminalInteractionSection({
           />
         </SearchableSetting>
 
+        <SearchableSetting
+          title={translate(
+            'components.settings.TerminalInteraction.copyTrimsGutter',
+            'Trim Gutter on Copy'
+          )}
+          description={translate(
+            'components.settings.TerminalInteraction.copyTrimsGutterDescription',
+            'Drop the left gutter agent output is painted behind, so copied text is not indented. Only the indent every selected line shares is removed.'
+          )}
+          keywords={[
+            'clipboard',
+            'copy',
+            'gutter',
+            'indent',
+            'margin',
+            'leading',
+            'whitespace',
+            'spaces',
+            'selection',
+            'paste'
+          ]}
+        >
+          <SettingsSwitchRow
+            label={translate(
+              'components.settings.TerminalInteraction.copyTrimsGutter',
+              'Trim Gutter on Copy'
+            )}
+            description={translate(
+              'components.settings.TerminalInteraction.copyTrimsGutterDescription',
+              'Drop the left gutter agent output is painted behind, so copied text is not indented. Only the indent every selected line shares is removed.'
+            )}
+            checked={settings.terminalCopyTrimsGutter}
+            onChange={() =>
+              updateSettings({
+                terminalCopyTrimsGutter: !settings.terminalCopyTrimsGutter
+              })
+            }
+          />
+        </SearchableSetting>
+
         <SearchableSetting
           id={OSC52_CLIPBOARD_SETTING_ID}
           title={translate(
diff --git a/src/renderer/src/components/settings/TerminalScrollSpeedSlider.tsx b/src/renderer/src/components/settings/TerminalScrollSpeedSlider.tsx
new file mode 100644
index 00000000000..6d8851a8c36
--- /dev/null
+++ b/src/renderer/src/components/settings/TerminalScrollSpeedSlider.tsx
@@ -0,0 +1,61 @@
+import { Slider } from '../ui/slider'
+import { Label } from '../ui/label'
+
+type ScrollSpeedSliderProps = {
+  label: string
+  description: string
+  value: number
+  min: number
+  max: number
+  step: number
+  suffix: string
+  onChange: (value: number) => void
+}
+
+function formatScrollSpeedValue(value: number): string {
+  return Number.isInteger(value)
+    ? String(value)
+    : value.toFixed(2).replace(/0+$/, '').replace(/\.$/, '')
+}
+
+export function ScrollSpeedSlider({
+  label,
+  description,
+  value,
+  min,
+  max,
+  step,
+  suffix,
+  onChange
+}: ScrollSpeedSliderProps): React.JSX.Element {
+  return (
+    <div className="rounded-md border border-border/60 bg-background/50 p-3">
+      <div className="flex items-start justify-between gap-3">
+        <div className="min-w-0 space-y-0.5">
+          <Label className="text-xs font-medium">{label}</Label>
+          <p className="text-[11px] leading-4 text-muted-foreground">{description}</p>
+        </div>
+        <span className="shrink-0 rounded-md border border-border/50 bg-muted/40 px-1.5 py-0.5 font-mono text-[11px] tabular-nums text-foreground">
+          {formatScrollSpeedValue(value)}
+          {suffix}
+        </span>
+      </div>
+      <Slider
+        className="mt-3"
+        min={min}
+        max={max}
+        step={step}
+        value={[value]}
+        onValueChange={([next]) => {
+          if (next !== undefined) {
+            onChange(next)
+          }
+        }}
+      />
+      <div className="mt-1 flex justify-between font-mono text-[10px] text-muted-foreground">
+        <span>{formatScrollSpeedValue(min)}</span>
+        <span>{formatScrollSpeedValue(max)}</span>
+      </div>
+    </div>
+  )
+}
diff --git a/src/renderer/src/components/settings/terminal-clipboard-search.ts b/src/renderer/src/components/settings/terminal-clipboard-search.ts
index 8cc00935d98..bb1a18e444c 100644
--- a/src/renderer/src/components/settings/terminal-clipboard-search.ts
+++ b/src/renderer/src/components/settings/terminal-clipboard-search.ts
@@ -119,5 +119,42 @@ export const getTerminalClipboardSearchEntries = createLocalizedCatalog(() => [
         'paste'
       )
     ]
+  },
+  {
+    title: translate(
+      'components.settings.TerminalInteraction.copyTrimsGutter',
+      'Trim Gutter on Copy'
+    ),
+    description: translate(
+      'components.settings.TerminalInteraction.copyTrimsGutterDescription',
+      'Drop the left gutter agent output is painted behind, so copied text is not indented. Only the indent every selected line shares is removed.'
+    ),
+    keywords: [
+      ...translateSearchKeyword(
+        'auto.components.settings.terminal.clipboard.search.10d73e22d3',
+        'clipboard'
+      ),
+      ...translateSearchKeyword(
+        'auto.components.settings.terminal.clipboard.search.a38508c419',
+        'copy'
+      ),
+      ...translateSearchKeyword('components.settings.terminal.clipboard.search.gutter', 'gutter'),
+      ...translateSearchKeyword('components.settings.terminal.clipboard.search.indent', 'indent'),
+      ...translateSearchKeyword('components.settings.terminal.clipboard.search.margin', 'margin'),
+      ...translateSearchKeyword('components.settings.terminal.clipboard.search.leading', 'leading'),
+      ...translateSearchKeyword(
+        'components.settings.terminal.clipboard.search.whitespace',
+        'whitespace'
+      ),
+      ...translateSearchKeyword('components.settings.terminal.clipboard.search.spaces', 'spaces'),
+      ...translateSearchKeyword(
+        'auto.components.settings.terminal.clipboard.search.c38c18be15',
+        'selection'
+      ),
+      ...translateSearchKeyword(
+        'auto.components.settings.terminal.clipboard.search.5fb3512e8c',
+        'paste'
+      )
+    ]
   }
 ])
diff --git a/src/renderer/src/components/terminal-pane/terminal-clipboard-selection-text.test.ts b/src/renderer/src/components/terminal-pane/terminal-clipboard-selection-text.test.ts
new file mode 100644
index 00000000000..2307831bf59
--- /dev/null
+++ b/src/renderer/src/components/terminal-pane/terminal-clipboard-selection-text.test.ts
@@ -0,0 +1,60 @@
+import { beforeEach, describe, expect, it, vi } from 'vitest'
+import type { GlobalSettings } from '../../../../shared/global-settings-types'
+
+const settings: { current: Partial<GlobalSettings> } = { current: {} }
+vi.mock('@/store', () => ({
+  useAppStore: { getState: () => ({ settings: settings.current }) }
+}))
+
+const { readTerminalClipboardSelection } = await import('./terminal-clipboard-selection-text')
+const { copyTerminalSelection } = await import('./terminal-selection-copy')
+
+// The gutter an agent CLI paints its message behind, as xterm reports it.
+const GUTTERED = ['  Retry limit is now 5.', '  Backoff starts at 2s.'].join('\n')
+const UNGUTTERED = ['Retry limit is now 5.', 'Backoff starts at 2s.'].join('\n')
+
+describe('readTerminalClipboardSelection', () => {
+  beforeEach(() => {
+    settings.current = {}
+  })
+
+  it('strips the gutter by default', () => {
+    expect(readTerminalClipboardSelection({ getSelection: () => GUTTERED })).toBe(UNGUTTERED)
+  })
+
+  it('strips the gutter when the setting is explicitly on', () => {
+    settings.current = { terminalCopyTrimsGutter: true }
+    expect(readTerminalClipboardSelection({ getSelection: () => GUTTERED })).toBe(UNGUTTERED)
+  })
+
+  it('copies screen cells verbatim when the setting is off', () => {
+    settings.current = { terminalCopyTrimsGutter: false }
+    expect(readTerminalClipboardSelection({ getSelection: () => GUTTERED })).toBe(GUTTERED)
+  })
+})
+
+describe('copyTerminalSelection gutter handling', () => {
+  beforeEach(() => {
+    settings.current = {}
+  })
+
+  it('writes the un-guttered text to the clipboard', async () => {
+    const writeClipboardText = vi.fn<(text: string) => Promise<void>>().mockResolvedValue()
+    await copyTerminalSelection({
+      terminal: { getSelection: () => GUTTERED, clearSelection: vi.fn() },
+      writeClipboardText
+    })
+    expect(writeClipboardText).toHaveBeenCalledWith(UNGUTTERED)
+  })
+
+  it('still reports no selection for an empty xterm selection', async () => {
+    const writeClipboardText = vi.fn<(text: string) => Promise<void>>().mockResolvedValue()
+    await expect(
+      copyTerminalSelection({
+        terminal: { getSelection: () => '', clearSelection: vi.fn() },
+        writeClipboardText
+      })
+    ).resolves.toBe(false)
+    expect(writeClipboardText).not.toHaveBeenCalled()
+  })
+})
diff --git a/src/renderer/src/components/terminal-pane/terminal-clipboard-selection-text.ts b/src/renderer/src/components/terminal-pane/terminal-clipboard-selection-text.ts
new file mode 100644
index 00000000000..5bc1b2b3c72
--- /dev/null
+++ b/src/renderer/src/components/terminal-pane/terminal-clipboard-selection-text.ts
@@ -0,0 +1,17 @@
+import type { Terminal } from '@xterm/xterm'
+import { useAppStore } from '@/store'
+import { stripTerminalSelectionGutter } from '../../../../shared/terminal-selection-gutter'
+
+/**
+ * The selection text every terminal clipboard path should write: screen cells
+ * minus the left gutter the agent CLI painted them behind (#19770).
+ */
+export function readTerminalClipboardSelection(terminal: Pick<Terminal, 'getSelection'>): string {
+  const selection = terminal.getSelection()
+  // Why `=== false`: profiles saved before the setting existed have no key, and
+  // they should trim like every new profile does.
+  if (useAppStore.getState().settings?.terminalCopyTrimsGutter === false) {
+    return selection
+  }
+  return stripTerminalSelectionGutter(selection)
+}
diff --git a/src/renderer/src/components/terminal-pane/terminal-native-copy-gutter.test.ts b/src/renderer/src/components/terminal-pane/terminal-native-copy-gutter.test.ts
new file mode 100644
index 00000000000..f6e618e168c
--- /dev/null
+++ b/src/renderer/src/components/terminal-pane/terminal-native-copy-gutter.test.ts
@@ -0,0 +1,81 @@
+// @vitest-environment happy-dom
+import { beforeEach, describe, expect, it, vi } from 'vitest'
+import type { GlobalSettings } from '../../../../shared/global-settings-types'
+
+const settings: { current: Partial<GlobalSettings> } = { current: {} }
+vi.mock('@/store', () => ({
+  useAppStore: { getState: () => ({ settings: settings.current }) }
+}))
+
+const { installTerminalNativeCopyGutterTrim } = await import('./terminal-native-copy-gutter')
+
+const GUTTERED = ['  Retry limit is now 5.', '  Backoff starts at 2s.'].join('\n')
+const UNGUTTERED = ['Retry limit is now 5.', 'Backoff starts at 2s.'].join('\n')
+
+function makeTerminal(selection: string) {
+  const element = document.createElement('div')
+  document.body.appendChild(element)
+  return {
+    element,
+    getSelection: () => selection,
+    hasSelection: () => selection.length > 0
+  }
+}
+
+function dispatchCopy(element: HTMLElement) {
+  const written = new Map<string, string>()
+  const event = new Event('copy', { bubbles: true, cancelable: true })
+  Object.defineProperty(event, 'clipboardData', {
+    value: { setData: (type: string, data: string) => written.set(type, data) }
+  })
+  element.dispatchEvent(event)
+  return { written, defaultPrevented: event.defaultPrevented }
+}
+
+describe('installTerminalNativeCopyGutterTrim', () => {
+  beforeEach(() => {
+    settings.current = {}
+    document.body.innerHTML = ''
+  })
+
+  // Why: xterm's own `copy` listener writes raw screen cells, so a native copy
+  // Orca does not bind (Ctrl+Insert on Windows/Linux) would carry the gutter.
+  it('writes the un-guttered text for a native copy event', () => {
+    const terminal = makeTerminal(GUTTERED)
+    installTerminalNativeCopyGutterTrim(terminal)
+    const { written, defaultPrevented } = dispatchCopy(terminal.element)
+    expect(written.get('text/plain')).toBe(UNGUTTERED)
+    expect(defaultPrevented).toBe(true)
+  })
+
+  it('honours the opt-out', () => {
+    settings.current = { terminalCopyTrimsGutter: false }
+    const terminal = makeTerminal(GUTTERED)
+    installTerminalNativeCopyGutterTrim(terminal)
+    expect(dispatchCopy(terminal.element).written.get('text/plain')).toBe(GUTTERED)
+  })
+
+  it('leaves an empty selection to the default handler', () => {
+    const terminal = makeTerminal('')
+    installTerminalNativeCopyGutterTrim(terminal)
+    const { written, defaultPrevented } = dispatchCopy(terminal.element)
+    expect(written.size).toBe(0)
+    expect(defaultPrevented).toBe(false)
+  })
+
+  it('stops writing once disposed', () => {
+    const terminal = makeTerminal(GUTTERED)
+    installTerminalNativeCopyGutterTrim(terminal).dispose()
+    expect(dispatchCopy(terminal.element).written.size).toBe(0)
+  })
+
+  it('is inert before xterm has opened an element', () => {
+    expect(() =>
+      installTerminalNativeCopyGutterTrim({
+        element: undefined,
+        getSelection: () => GUTTERED,
+        hasSelection: () => true
+      }).dispose()
+    ).not.toThrow()
+  })
+})
diff --git a/src/renderer/src/components/terminal-pane/terminal-native-copy-gutter.ts b/src/renderer/src/components/terminal-pane/terminal-native-copy-gutter.ts
new file mode 100644
index 00000000000..1e12de1bc5f
--- /dev/null
+++ b/src/renderer/src/components/terminal-pane/terminal-native-copy-gutter.ts
@@ -0,0 +1,32 @@
+import type { IDisposable, Terminal } from '@xterm/xterm'
+import { readTerminalClipboardSelection } from './terminal-clipboard-selection-text'
+
+type NativeCopyTerminal = Pick<Terminal, 'getSelection' | 'hasSelection'> & {
+  element?: HTMLElement
+}
+
+/**
+ * xterm binds its own DOM `copy` listener that writes raw screen cells
+ * (CoreBrowserTerminal `_initGlobal`). Orca's own chords never reach it — they
+ * preventDefault in keydown — but a native copy Orca does not bind still does:
+ * Ctrl+Insert is a Chromium copy accelerator on Windows/Linux and is not in
+ * `terminal.copySelection`'s bindings, so it would carry the gutter (#19770).
+ * Capture phase, so this wins when the event targets the helper textarea and
+ * xterm's element-level listener is next in line.
+ */
+export function installTerminalNativeCopyGutterTrim(terminal: NativeCopyTerminal): IDisposable {
+  const element = terminal.element
+  if (!element) {
+    return { dispose: () => {} }
+  }
+  const onCopy = (event: ClipboardEvent): void => {
+    if (!terminal.hasSelection() || !event.clipboardData) {
+      return
+    }
+    event.clipboardData.setData('text/plain', readTerminalClipboardSelection(terminal))
+    event.preventDefault()
+    event.stopImmediatePropagation()
+  }
+  element.addEventListener('copy', onCopy, { capture: true })
+  return { dispose: () => element.removeEventListener('copy', onCopy, { capture: true }) }
+}
diff --git a/src/renderer/src/components/terminal-pane/terminal-pane-menu-copy-actions.ts b/src/renderer/src/components/terminal-pane/terminal-pane-menu-copy-actions.ts
index 417f920af5c..d8f5d8f0733 100644
--- a/src/renderer/src/components/terminal-pane/terminal-pane-menu-copy-actions.ts
+++ b/src/renderer/src/components/terminal-pane/terminal-pane-menu-copy-actions.ts
@@ -4,13 +4,14 @@ import { makePaneKey } from '../../../../shared/stable-pane-id'
 import { translate } from '@/i18n/i18n'
 import { copyTerminalHandleForPane } from './terminal-handle-copy'
 import { runTerminalCopy, runTerminalIdentityCopy } from './terminal-copy-rejection-guards'
+import { readTerminalClipboardSelection } from './terminal-clipboard-selection-text'
 
 export const copyTerminalPaneMenuSelection = async (pane: ManagedPane | null): Promise<void> => {
   if (!pane) {
     return
   }
   await runTerminalCopy({
-    selection: pane.terminal.getSelection(),
+    selection: readTerminalClipboardSelection(pane.terminal),
     writeClipboardText: window.api.ui.writeTerminalClipboardText,
     // Why: Radix returns focus to the menu trigger (the pane container) on
     // close, but xterm.js only accepts input when its own helper textarea is
diff --git a/src/renderer/src/components/terminal-pane/terminal-pane-mount-cleanup.ts b/src/renderer/src/components/terminal-pane/terminal-pane-mount-cleanup.ts
index 69c7b71c380..d576576f900 100644
--- a/src/renderer/src/components/terminal-pane/terminal-pane-mount-cleanup.ts
+++ b/src/renderer/src/components/terminal-pane/terminal-pane-mount-cleanup.ts
@@ -61,6 +61,7 @@ export function cleanupTerminalPaneMount(args: {
   disposeAll(refs.fileLinkClickFallbackDisposablesRef.current)
   disposeAll(refs.httpLinkClickFallbackDisposablesRef.current)
   disposeAll(refs.selectionDisposablesRef.current)
+  disposeAll(refs.nativeCopyDisposablesRef.current)
   for (const timer of refs.selectionCaptureTimersRef.current.values()) {
     window.clearTimeout(timer)
   }
diff --git a/src/renderer/src/components/terminal-pane/terminal-pane-pane-closed.ts b/src/renderer/src/components/terminal-pane/terminal-pane-pane-closed.ts
index 7859c37c330..a70545c173c 100644
--- a/src/renderer/src/components/terminal-pane/terminal-pane-pane-closed.ts
+++ b/src/renderer/src/components/terminal-pane/terminal-pane-pane-closed.ts
@@ -57,6 +57,7 @@ export function createTerminalPaneClosedHandler(
     disposeMapEntry(refs.fileLinkClickFallbackDisposablesRef.current, paneId)
     disposeMapEntry(refs.httpLinkClickFallbackDisposablesRef.current, paneId)
     disposeMapEntry(refs.selectionDisposablesRef.current, paneId)
+    disposeMapEntry(refs.nativeCopyDisposablesRef.current, paneId)
     disposeMapEntry(refs.imeCompositionDisposablesRef.current, paneId)
     disposeMapEntry(refs.imeNativeTextForwarderDisposablesRef.current, paneId)
     const timer = refs.selectionCaptureTimersRef.current.get(paneId)
diff --git a/src/renderer/src/components/terminal-pane/terminal-pane-pane-links.ts b/src/renderer/src/components/terminal-pane/terminal-pane-pane-links.ts
index f0eb3ae6c0e..3db5e48fdcf 100644
--- a/src/renderer/src/components/terminal-pane/terminal-pane-pane-links.ts
+++ b/src/renderer/src/components/terminal-pane/terminal-pane-pane-links.ts
@@ -18,6 +18,8 @@ import { installTerminalLinkPointerGesture } from './terminal-link-pointer-gestu
 import { installHttpLinkClickFallback } from './terminal-url-link-hit-testing'
 import { handleOscLink } from './terminal-osc-link-routing'
 import { copyTerminalSelection } from './terminal-selection-copy'
+import { readTerminalClipboardSelection } from './terminal-clipboard-selection-text'
+import { installTerminalNativeCopyGutterTrim } from './terminal-native-copy-gutter'
 import { installMouseHideWhileTyping } from './mouse-hide-while-typing'
 import { isPrimarySelectionEnabled, setPrimarySelectionText } from '@/lib/primary-selection'
 import {
@@ -39,6 +41,7 @@ type PaneLinkContext = {
     | 'fileLinkClickFallbackDisposablesRef'
     | 'httpLinkClickFallbackDisposablesRef'
     | 'selectionDisposablesRef'
+    | 'nativeCopyDisposablesRef'
     | 'selectionCaptureTimersRef'
     | 'mouseHideDisposablesRef'
   >
@@ -113,6 +116,10 @@ export function installTerminalPaneLinkHandling(context: PaneLinkContext): void
   )
   seedStartupSessionRestoredBanner(ptyStartup, pane.id, onShowSessionRestoredBanner)
 
+  refs.nativeCopyDisposablesRef.current.set(
+    pane.id,
+    installTerminalNativeCopyGutterTrim(pane.terminal)
+  )
   refs.selectionDisposablesRef.current.set(
     pane.id,
     pane.terminal.onSelectionChange(() => {
@@ -144,7 +151,7 @@ export function installTerminalPaneLinkHandling(context: PaneLinkContext): void
           if (terminalSelectionExceedsPrimaryLimit(pane.terminal)) {
             return
           }
-          const selection = pane.terminal.getSelection()
+          const selection = readTerminalClipboardSelection(pane.terminal)
           if (selection) {
             setPrimarySelectionText(selection)
           }
diff --git a/src/renderer/src/components/terminal-pane/terminal-selection-copy.ts b/src/renderer/src/components/terminal-pane/terminal-selection-copy.ts
index 5123a80079d..7ea53cdb43e 100644
--- a/src/renderer/src/components/terminal-pane/terminal-selection-copy.ts
+++ b/src/renderer/src/components/terminal-pane/terminal-selection-copy.ts
@@ -1,4 +1,5 @@
 import type { Terminal } from '@xterm/xterm'
+import { readTerminalClipboardSelection } from './terminal-clipboard-selection-text'
 
 type TerminalSelectionCopyOptions = {
   terminal: Pick<Terminal, 'getSelection' | 'clearSelection'>
@@ -11,7 +12,7 @@ export async function copyTerminalSelection({
   writeClipboardText,
   clearSelectionOnSuccess = false
 }: TerminalSelectionCopyOptions): Promise<boolean> {
-  const selection = terminal.getSelection()
+  const selection = readTerminalClipboardSelection(terminal)
   if (!selection) {
     return false
   }
diff --git a/src/renderer/src/components/terminal-pane/use-terminal-pane-lifecycle-refs.ts b/src/renderer/src/components/terminal-pane/use-terminal-pane-lifecycle-refs.ts
index 53c8de6618f..01f13488486 100644
--- a/src/renderer/src/components/terminal-pane/use-terminal-pane-lifecycle-refs.ts
+++ b/src/renderer/src/components/terminal-pane/use-terminal-pane-lifecycle-refs.ts
@@ -21,6 +21,7 @@ export function useTerminalPaneLifecycleRefs() {
       new Map<number, ReturnType<typeof installHttpLinkClickFallback>>()
     ),
     selectionDisposablesRef: useRef(new Map<number, IDisposable>()),
+    nativeCopyDisposablesRef: useRef(new Map<number, IDisposable>()),
     selectionCaptureTimersRef: useRef(new Map<number, number>()),
     osc52DisposablesRef: useRef(new Map<number, IDisposable>()),
     osc7DisposablesRef: useRef(new Map<number, IDisposable>()),
diff --git a/src/renderer/src/i18n/locales/en.json b/src/renderer/src/i18n/locales/en.json
index f2c94ba41da..b0ba0c8f1a9 100644
--- a/src/renderer/src/i18n/locales/en.json
+++ b/src/renderer/src/i18n/locales/en.json
@@ -17607,6 +17607,24 @@
         "copySessionIdSuccess": "Session ID copied",
         "copySessionIdError": "Unable to copy session ID"
       }
+    },
+    "settings": {
+      "TerminalInteraction": {
+        "copyTrimsGutter": "Trim Gutter on Copy",
+        "copyTrimsGutterDescription": "Drop the left gutter agent output is painted behind, so copied text is not indented. Only the indent every selected line shares is removed."
+      },
+      "terminal": {
+        "clipboard": {
+          "search": {
+            "gutter": "gutter",
+            "indent": "indent",
+            "margin": "margin",
+            "leading": "leading",
+            "whitespace": "whitespace",
+            "spaces": "spaces"
+          }
+        }
+      }
     }
   },
   "dashboardPopout": {
diff --git a/src/shared/default-global-settings.ts b/src/shared/default-global-settings.ts
index c9b7a08928a..c11d05dc753 100644
--- a/src/shared/default-global-settings.ts
+++ b/src/shared/default-global-settings.ts
@@ -105,6 +105,9 @@ export function buildDefaultSettings(args: {
     // Why: default-on everywhere so it round-trips across platforms; only darwin acts on it.
     showMenuBarIcon: true,
     terminalClipboardOnSelect: false,
+    // Why: only the run of spaces shared by every selected line is dropped, so
+    // relative indentation survives and the clipboard loses only the gutter.
+    terminalCopyTrimsGutter: true,
     // Why: default on so Zellij/tmux/nvim copy works out of the box. Query
     // replies stay disabled and payload size is capped in the OSC 52 handler.
     // This default only covers new profiles; existing ones persisted `false`
diff --git a/src/shared/global-settings-types.ts b/src/shared/global-settings-types.ts
index 5aac39c52ca..e65fec28c39 100644
--- a/src/shared/global-settings-types.ts
+++ b/src/shared/global-settings-types.ts
@@ -183,6 +183,8 @@ export type GlobalSettings = {
   terminalFocusFollowsMouse: boolean
   /** X11/gnome-terminal "copy on select": selecting text auto-copies to the clipboard; default off. */
   terminalClipboardOnSelect: boolean
+  /** Drops the left gutter agent CLIs paint their output behind when copying a terminal selection; default on. */
+  terminalCopyTrimsGutter: boolean
   /** Enables OSC 52 clipboard writes for TUIs (tmux/Zellij/nvim, incl. over SSH); default on. Clipboard *queries* stay blocked and payload size is capped, so this is write-only exposure. */
   terminalAllowOsc52Clipboard: boolean
   /** One-shot stamp: profiles saved under the old off default get flipped on once, after which an explicit opt-out sticks. */
diff --git a/src/shared/terminal-selection-gutter.test.ts b/src/shared/terminal-selection-gutter.test.ts
new file mode 100644
index 00000000000..9a70bc7013b
--- /dev/null
+++ b/src/shared/terminal-selection-gutter.test.ts
@@ -0,0 +1,96 @@
+import { describe, expect, it } from 'vitest'
+import { stripTerminalSelectionGutter } from './terminal-selection-gutter'
+
+// Shape agent CLIs paint: a marker column, then continuation lines behind a
+// two-space gutter. Selecting the body is what users copy to paste elsewhere.
+const AGENT_MESSAGE_BODY = [
+  '  Thanks for flagging this. The retry limit is now 5, and the backoff',
+  '  starts at 2s instead of 500ms.',
+  '',
+  '  Let me know if anything still looks off.'
+].join('\n')
+
+describe('stripTerminalSelectionGutter', () => {
+  it('drops the gutter agent output is painted behind', () => {
+    expect(stripTerminalSelectionGutter(AGENT_MESSAGE_BODY)).toBe(
+      [
+        'Thanks for flagging this. The retry limit is now 5, and the backoff',
+        'starts at 2s instead of 500ms.',
+        '',
+        'Let me know if anything still looks off.'
+      ].join('\n')
+    )
+  })
+
+  it('drops the gutter from a single wrapped line', () => {
+    expect(stripTerminalSelectionGutter('  one logical line, joined by xterm')).toBe(
+      'one logical line, joined by xterm'
+    )
+  })
+
+  it('keeps relative indentation inside the gutter', () => {
+    const nested = ['  def run():', '      return 1', '', '  run()'].join('\n')
+    expect(stripTerminalSelectionGutter(nested)).toBe(
+      ['def run():', '    return 1', '', 'run()'].join('\n')
+    )
+  })
+
+  it('leaves a selection that starts mid-line untouched', () => {
+    const midLine = ['answer starts here', '  and continues', '  and ends'].join('\n')
+    expect(stripTerminalSelectionGutter(midLine)).toBe(midLine)
+  })
+
+  it('leaves unindented output untouched', () => {
+    const shellOutput = ['$ git status', 'On branch main', 'nothing to commit'].join('\n')
+    expect(stripTerminalSelectionGutter(shellOutput)).toBe(shellOutput)
+  })
+
+  it('ignores blank lines when measuring the gutter', () => {
+    expect(stripTerminalSelectionGutter(['  a', '', '  b'].join('\n'))).toBe(
+      ['a', '', 'b'].join('\n')
+    )
+  })
+
+  it('ignores whitespace-only lines when measuring the gutter', () => {
+    expect(stripTerminalSelectionGutter(['    a', ' ', '    b'].join('\n'))).toBe(
+      ['a', '', 'b'].join('\n')
+    )
+  })
+
+  it('leaves an all-whitespace selection untouched', () => {
+    expect(stripTerminalSelectionGutter('   \n  \n')).toBe('   \n  \n')
+  })
+
+  it('preserves the CRLF joins xterm emits on Windows', () => {
+    expect(stripTerminalSelectionGutter('  first\r\n  second\r\n')).toBe('first\r\nsecond\r\n')
+  })
+
+  // Regression: a blank CRLF row is '\r', which reads as a zero-indent content
+  // row unless the CR is split off first — that would cancel the gutter on
+  // Windows only.
+  it('still finds the gutter across a blank CRLF row', () => {
+    expect(stripTerminalSelectionGutter('  first\r\n\r\n  second\r\n')).toBe(
+      'first\r\n\r\nsecond\r\n'
+    )
+  })
+
+  it('leaves wide characters and emoji in the content alone', () => {
+    expect(
+      stripTerminalSelectionGutter(['  変更を適用しました 🎉', '  お疲れさま'].join('\n'))
+    ).toBe(['変更を適用しました 🎉', 'お疲れさま'].join('\n'))
+  })
+
+  it('does not strip past a shorter line', () => {
+    const uneven = ['    deep', '  shallow'].join('\n')
+    expect(stripTerminalSelectionGutter(uneven)).toBe(['  deep', 'shallow'].join('\n'))
+  })
+
+  it('is a no-op on an empty selection', () => {
+    expect(stripTerminalSelectionGutter('')).toBe('')
+  })
+
+  it('leaves tab-indented text alone (terminal cells never hold tabs)', () => {
+    const tabbed = ['\tone', '\ttwo'].join('\n')
+    expect(stripTerminalSelectionGutter(tabbed)).toBe(tabbed)
+  })
+})
diff --git a/src/shared/terminal-selection-gutter.ts b/src/shared/terminal-selection-gutter.ts
new file mode 100644
index 00000000000..ad30ce0a839
--- /dev/null
+++ b/src/shared/terminal-selection-gutter.ts
@@ -0,0 +1,57 @@
+// Why: an xterm selection is a rectangle of screen cells, not logical text.
+// Agent CLIs paint their messages behind a fixed left gutter, so every copied
+// line carried that gutter into the clipboard and pasted replies came out
+// indented (#19770).
+//
+// Only the run of spaces that *every* non-blank line shares is removed, so
+// relative indentation — nested bullets, fenced code, YAML — survives. A
+// selection that starts mid-line, or that covers any column-0 line, shares a
+// run of zero and comes back untouched.
+
+// Spaces are the whole alphabet here: terminal cells never hold tabs (the
+// emulator expands them), and xterm's selectionText getter already folds every
+// NBSP cell to a plain space on its way out (SelectionService.ts, the
+// ALL_NON_BREAKING_SPACE_REGEX replace) — that is the selection path, not the
+// input path.
+const LEADING_SPACES = /^ */
+
+type SelectionLine = { indent: number; text: string; terminator: string }
+
+// xterm joins rows with CRLF on Windows, so split('\n') leaves the CR behind.
+// It has to travel with the line: without it a blank CRLF row looks like a
+// zero-indent content row and would cancel the gutter on Windows only.
+function parseLine(rawLine: string): SelectionLine {
+  const carriageReturn = rawLine.endsWith('\r')
+  const text = carriageReturn ? rawLine.slice(0, -1) : rawLine
+  return {
+    indent: LEADING_SPACES.exec(text)?.[0].length ?? 0,
+    text,
+    terminator: carriageReturn ? '\r' : ''
+  }
+}
+
+function measureGutter(lines: readonly SelectionLine[]): number {
+  let gutter = Number.POSITIVE_INFINITY
+  for (const { indent, text } of lines) {
+    // Blank and whitespace-only lines are evidence of nothing either way.
+    if (indent === text.length) {
+      continue
+    }
+    gutter = Math.min(gutter, indent)
+    if (gutter === 0) {
+      return 0
+    }
+  }
+  return Number.isFinite(gutter) ? gutter : 0
+}
+
+export function stripTerminalSelectionGutter(selection: string): string {
+  const lines = selection.split('\n').map(parseLine)
+  const gutter = measureGutter(lines)
+  if (gutter === 0) {
+    return selection
+  }
+  return lines
+    .map(({ indent, text, terminator }) => text.slice(Math.min(indent, gutter)) + terminator)
+    .join('\n')
+}