diff --git a/src/main/ipc/workspace-cleanup.ts b/src/main/ipc/workspace-cleanup.ts
index 49f553d36f2..829a1918470 100644
--- a/src/main/ipc/workspace-cleanup.ts
+++ b/src/main/ipc/workspace-cleanup.ts
@@ -57,10 +57,7 @@ export function registerWorkspaceCleanupHandlers(
   )
 
   ipcMain.handle('workspaceCleanup:dismiss', (_event, args: WorkspaceCleanupDismissArgs) => {
-    // Why spread the whole record: updateUI replaces `workspaceCleanup` wholesale,
-    // so writing dismissals alone would erase the persisted browse state.
-    const currentState = store.getUI().workspaceCleanup
-    const next = { ...currentState?.dismissals }
+    const next = { ...store.getUI().workspaceCleanup?.dismissals }
     for (const dismissal of args.dismissals ?? []) {
       if (
         dismissal &&
@@ -71,13 +68,11 @@ export function registerWorkspaceCleanupHandlers(
         next[dismissal.worktreeId] = dismissal
       }
     }
-    store.updateUI({ workspaceCleanup: { ...currentState, dismissals: next } })
+    store.updateUI({ workspaceCleanup: { dismissals: next } })
   })
 
   ipcMain.handle('workspaceCleanup:clearDismissals', () => {
-    store.updateUI({
-      workspaceCleanup: { ...store.getUI().workspaceCleanup, dismissals: {} }
-    })
+    store.updateUI({ workspaceCleanup: { dismissals: {} } })
   })
 
   ipcMain.handle(
diff --git a/src/main/persistence.test.ts b/src/main/persistence.test.ts
index b59ca6f5986..de1bf8aaff3 100644
--- a/src/main/persistence.test.ts
+++ b/src/main/persistence.test.ts
@@ -41,6 +41,7 @@ import { SshConnectionStore } from './ssh/ssh-connection-store'
 import { setSourceControlActionDefault } from '../shared/source-control-ai-actions'
 import { LEGACY_DEFAULT_SSH_RELAY_GRACE_PERIOD_SECONDS } from '../shared/ssh-types'
 import { closeTerminalTabInWorkspaceSession } from '../shared/workspace-session-terminal-tab-close'
+import { createDefaultWorkspaceCleanupBrowseState } from '../shared/workspace-cleanup-browse-state'
 
 // Shared mutable state so the electron mock can reference a per-test directory
 const testState = { dir: '' }
@@ -6495,6 +6496,29 @@ describe('Store', () => {
     })
   })
 
+  it('updateUI preserves browse state when a legacy peer publishes dismissals only', async () => {
+    const store = await createStore()
+    const browse = createDefaultWorkspaceCleanupBrowseState()
+    browse.filters.query = 'stale'
+
+    store.updateUI({ workspaceCleanup: { dismissals: {}, browse } })
+    store.updateUI({
+      workspaceCleanup: {
+        dismissals: {
+          'wt-1': {
+            worktreeId: 'wt-1',
+            dismissedAt: 1700000000000,
+            fingerprint: 'fp-1',
+            classifierVersion: 2
+          }
+        }
+      }
+    })
+
+    expect(store.getUI().workspaceCleanup?.browse).toEqual(browse)
+    expect(store.getUI().workspaceCleanup?.dismissals).toHaveProperty('wt-1')
+  })
+
   it('updateUI merges contextual tour seen ids instead of replacing stale snapshots', async () => {
     const store = await createStore()
 
diff --git a/src/main/persistence.ts b/src/main/persistence.ts
index 8a74aea7b8a..d6791ebc9be 100644
--- a/src/main/persistence.ts
+++ b/src/main/persistence.ts
@@ -176,6 +176,7 @@ import {
 } from '../shared/cross-platform-path'
 import { normalizeTerminalQuickCommands } from '../shared/terminal-quick-commands'
 import { normalizeTaskProviderSettings } from '../shared/task-providers'
+import { mergeWorkspaceCleanupUIState } from '../shared/workspace-cleanup-ui-state'
 import { normalizeAutoRenameBranchFromWorkDefaultOn } from '../shared/auto-rename-branch-from-work-settings'
 import {
   addMobilePairingCustomAddress,
@@ -6041,6 +6042,10 @@ export class Store {
     const nextUI = {
       ...currentUI,
       ...durableUpdates,
+      workspaceCleanup: mergeWorkspaceCleanupUIState(
+        currentUI.workspaceCleanup,
+        durableUpdates.workspaceCleanup
+      ),
       groupBy: durableUpdates.groupBy
         ? normalizeGroupBy(durableUpdates.groupBy)
         : normalizeGroupBy(this.state.ui?.groupBy),
diff --git a/src/renderer/src/i18n/locales/en.json b/src/renderer/src/i18n/locales/en.json
index 9d250a74956..ed8161ebd53 100644
--- a/src/renderer/src/i18n/locales/en.json
+++ b/src/renderer/src/i18n/locales/en.json
@@ -15054,7 +15054,6 @@
           "retainedDoneAgents": "Finished agent transcripts",
           "contextPresence": "Open tabs, terminals, comments",
           "completelyEmpty": "Nothing left to lose",
-          "presetModified": "edited",
           "noWorkspaces": "No workspaces found.",
           "noMatches": "No workspaces match these filters.",
           "noMatchesDescription": "Every workspace is in one list — widen a facet or clear the filters.",
diff --git a/src/renderer/src/store/slices/workspace-cleanup-browse.ts b/src/renderer/src/store/slices/workspace-cleanup-browse.ts
index 91134db96fa..9e917284912 100644
--- a/src/renderer/src/store/slices/workspace-cleanup-browse.ts
+++ b/src/renderer/src/store/slices/workspace-cleanup-browse.ts
@@ -31,8 +31,8 @@ export const createWorkspaceCleanupBrowseSlice: StateCreator<
     }
     persistTimer = setTimeout(() => {
       persistTimer = null
-      // Why dismissals ride along: main replaces `workspaceCleanup` wholesale on
-      // ui.set, so a browse-only payload would erase every dismissal.
+      // Why dismissals ride along: the legacy wire schema requires the field,
+      // while `browse` stays optional for older clients.
       window.api.ui
         .set({
           workspaceCleanup: {
diff --git a/src/renderer/src/web/web-preload-api.ts b/src/renderer/src/web/web-preload-api.ts
index c90c7cd95ec..31cbdca057c 100644
--- a/src/renderer/src/web/web-preload-api.ts
+++ b/src/renderer/src/web/web-preload-api.ts
@@ -146,6 +146,7 @@ import {
   parseRuntimeNativeChatTurnLifecycle
 } from '@/components/native-chat/native-chat-runtime-contract'
 import { createWebFileMutationMethods } from './web-file-mutation-methods'
+import { mergeWorkspaceCleanupUIState } from '../../../shared/workspace-cleanup-ui-state'
 
 const SETTINGS_STORAGE_KEY = 'orca.web.settings.v1'
 const UI_STORAGE_KEY = 'orca.web.ui.v1'
@@ -3916,6 +3917,10 @@ function mergeWebUIState(
   return {
     ...base,
     ...safeUpdates,
+    workspaceCleanup: mergeWorkspaceCleanupUIState(
+      base.workspaceCleanup,
+      safeUpdates.workspaceCleanup
+    ),
     worktreeCardProperties: normalizeWorktreeCardProperties(
       safeUpdates.worktreeCardProperties ?? base.worktreeCardProperties
     ),
diff --git a/src/shared/workspace-cleanup-browse-state-persistence.test.ts b/src/shared/workspace-cleanup-browse-state-persistence.test.ts
index 251c5c25db0..d0fad16e1c1 100644
--- a/src/shared/workspace-cleanup-browse-state-persistence.test.ts
+++ b/src/shared/workspace-cleanup-browse-state-persistence.test.ts
@@ -55,6 +55,22 @@ describe('workspace cleanup browse state persistence', () => {
     expect(normalized).not.toHaveProperty('unknownTopLevelField')
   })
 
+  it('drops invalid persisted host ids without losing valid SSH and runtime hosts', () => {
+    const normalized = normalizeWorkspaceCleanupBrowseState({
+      filters: {
+        location: {
+          hostIds: ['local', 'ssh:build%20box', 'not-a-host', 'runtime:linux', 'ssh:']
+        }
+      }
+    })
+
+    expect(normalized.filters.location.hostIds).toEqual([
+      'local',
+      'ssh:build%20box',
+      'runtime:linux'
+    ])
+  })
+
   it.each([null, undefined, 'corrupt', 42, [], { filters: 'nonsense' }])(
     'never throws on a corrupt blob (%p)',
     (value) => {
diff --git a/src/shared/workspace-cleanup-filter-state-codec.ts b/src/shared/workspace-cleanup-filter-state-codec.ts
index 5465adc75d2..5af505a281e 100644
--- a/src/shared/workspace-cleanup-filter-state-codec.ts
+++ b/src/shared/workspace-cleanup-filter-state-codec.ts
@@ -1,4 +1,4 @@
-import type { ExecutionHostId } from './execution-host'
+import { normalizeExecutionHostId, type ExecutionHostId } from './execution-host'
 import type { HostedReviewProvider } from './hosted-review'
 import {
   WORKSPACE_CLEANUP_AGENT_STATE_VALUES,
@@ -99,7 +99,7 @@ export function normalizeWorkspaceCleanupFilterState(value: unknown): WorkspaceC
       completelyEmpty: asBoolean(context.completelyEmpty, base.context.completelyEmpty)
     },
     location: {
-      hostIds: asStringList(location.hostIds) as ExecutionHostId[],
+      hostIds: asExecutionHostIdList(location.hostIds),
       repoIds: asStringList(location.repoIds),
       pathPrefix: asString(location.pathPrefix, base.location.pathPrefix)
     },
@@ -199,6 +199,23 @@ export function asStringList(value: unknown): string[] {
   return [...seen]
 }
 
+function asExecutionHostIdList(value: unknown): ExecutionHostId[] {
+  if (!Array.isArray(value)) {
+    return []
+  }
+  const result = new Set<ExecutionHostId>()
+  for (const entry of value) {
+    if (typeof entry !== 'string') {
+      continue
+    }
+    const hostId = normalizeExecutionHostId(entry)
+    if (hostId) {
+      result.add(hostId)
+    }
+  }
+  return [...result]
+}
+
 function asTriState(
   value: unknown,
   fallback: WorkspaceCleanupFilterState['status']['archived']
diff --git a/src/shared/workspace-cleanup-ui-state.test.ts b/src/shared/workspace-cleanup-ui-state.test.ts
new file mode 100644
index 00000000000..12aef389652
--- /dev/null
+++ b/src/shared/workspace-cleanup-ui-state.test.ts
@@ -0,0 +1,50 @@
+import { describe, expect, it } from 'vitest'
+import { createDefaultWorkspaceCleanupBrowseState } from './workspace-cleanup-browse-state'
+import { mergeWorkspaceCleanupUIState } from './workspace-cleanup-ui-state'
+
+describe('workspace cleanup UI state', () => {
+  it('keeps browse state when a legacy peer publishes dismissals only', () => {
+    const browse = createDefaultWorkspaceCleanupBrowseState()
+    browse.filters.query = 'stale'
+
+    expect(
+      mergeWorkspaceCleanupUIState(
+        { dismissals: {}, browse },
+        {
+          dismissals: {
+            'wt-1': {
+              worktreeId: 'wt-1',
+              dismissedAt: 1700000000000,
+              fingerprint: 'fp-1',
+              classifierVersion: 2
+            }
+          }
+        }
+      )
+    ).toEqual({
+      dismissals: {
+        'wt-1': {
+          worktreeId: 'wt-1',
+          dismissedAt: 1700000000000,
+          fingerprint: 'fp-1',
+          classifierVersion: 2
+        }
+      },
+      browse
+    })
+  })
+
+  it('accepts browse state published by a compatible peer', () => {
+    const current = createDefaultWorkspaceCleanupBrowseState()
+    current.filters.query = 'local'
+    const incoming = createDefaultWorkspaceCleanupBrowseState()
+    incoming.filters.query = 'host'
+
+    expect(
+      mergeWorkspaceCleanupUIState(
+        { dismissals: {}, browse: current },
+        { dismissals: {}, browse: incoming }
+      )?.browse
+    ).toBe(incoming)
+  })
+})
diff --git a/src/shared/workspace-cleanup-ui-state.ts b/src/shared/workspace-cleanup-ui-state.ts
new file mode 100644
index 00000000000..a674810c590
--- /dev/null
+++ b/src/shared/workspace-cleanup-ui-state.ts
@@ -0,0 +1,15 @@
+import type { WorkspaceCleanupUIState } from './workspace-cleanup'
+
+/** Keep browse state when an older client or host publishes dismissals only. */
+export function mergeWorkspaceCleanupUIState(
+  current: WorkspaceCleanupUIState | undefined,
+  incoming: WorkspaceCleanupUIState | undefined
+): WorkspaceCleanupUIState | undefined {
+  if (!incoming) {
+    return current
+  }
+  return {
+    ...current,
+    ...incoming
+  }
+}