fix(desktop): preserve dirty inline edits on blur

apps/desktop/src/components/assistant-ui/thread/user-edit-composer.tsx

@@ -80,6 +80,10 @@ export const UserEditComposer: FC<UserEditComposerProps> = ({ cwd, gateway, sess
   const draft = useAuiState(s => s.composer.text)
   const rootRef = useRef<HTMLDivElement | null>(null)
   const editorRef = useRef<HTMLDivElement | null>(null)
+  // Capture the original draft immediately before the first edit. The runtime
+  // may hydrate composer.text after this component's first render, so taking a
+  // mount-time snapshot can incorrectly classify every later blur as dirty.
+  const initialDraftRef = useRef<string | null>(null)
   const draftRef = useRef(draft)
   const dragDepthRef = useRef(0)
   const [dragActive, setDragActive] = useState(false)
@@ -120,6 +124,12 @@ export const UserEditComposer: FC<UserEditComposerProps> = ({ cwd, gateway, sess
     setFocusRequestId(id => id + 1)
   }, [])
 
+  const rememberInitialDraft = useCallback(() => {
+    if (initialDraftRef.current === null) {
+      initialDraftRef.current = draftRef.current
+    }
+  }, [])
+
   const appendExternalText = useCallback(
     (text: string, mode: ComposerInsertMode) => {
       const value = text.trim()
@@ -128,6 +138,7 @@ export const UserEditComposer: FC<UserEditComposerProps> = ({ cwd, gateway, sess
         return
       }
 
+      rememberInitialDraft()
       const base = mode === 'inline' ? draftRef.current.trimEnd() : draftRef.current
       const sep = mode === 'inline' ? (base ? ' ' : '') : base && !base.endsWith('\n') ? '\n\n' : ''
       const next = `${base}${sep}${value}`
@@ -144,7 +155,7 @@ export const UserEditComposer: FC<UserEditComposerProps> = ({ cwd, gateway, sess
 
       setFocusRequestId(id => id + 1)
     },
-    [aui]
+    [aui, rememberInitialDraft]
   )
 
   useEffect(() => {
@@ -263,6 +274,7 @@ export const UserEditComposer: FC<UserEditComposerProps> = ({ cwd, gateway, sess
         return
       }
 
+      rememberInitialDraft()
       const serialized = hermesDirectiveFormatter.serialize(item)
       const starter = serialized.endsWith(':')
       const text = starter || serialized.endsWith(' ') ? serialized : `${serialized} `
@@ -312,7 +324,7 @@ export const UserEditComposer: FC<UserEditComposerProps> = ({ cwd, gateway, sess
       document.execCommand('insertText', false, text)
       finish()
     },
-    [aui, closeTrigger, refreshTrigger, requestEditFocus, trigger]
+    [aui, closeTrigger, refreshTrigger, rememberInitialDraft, requestEditFocus, trigger]
   )
 
   const insertRefStrings = useCallback(
@@ -329,13 +341,14 @@ export const UserEditComposer: FC<UserEditComposerProps> = ({ cwd, gateway, sess
         return false
       }
 
+      rememberInitialDraft()
       draftRef.current = nextDraft
       aui.composer().setText(nextDraft)
       requestEditFocus()
 
       return true
     },
-    [aui, requestEditFocus]
+    [aui, rememberInitialDraft, requestEditFocus]
   )
 
   const insertDroppedRefs = useCallback(
@@ -473,6 +486,7 @@ export const UserEditComposer: FC<UserEditComposerProps> = ({ cwd, gateway, sess
       editor.replaceChildren()
     }
 
+    rememberInitialDraft()
     syncDraftFromEditor(editor)
     window.setTimeout(refreshTrigger, 0)
   }
@@ -487,6 +501,7 @@ export const UserEditComposer: FC<UserEditComposerProps> = ({ cwd, gateway, sess
     }
 
     event.preventDefault()
+    rememberInitialDraft()
     document.execCommand('insertText', false, pastedText)
     syncDraftFromEditor(event.currentTarget)
   }
@@ -518,11 +533,26 @@ export const UserEditComposer: FC<UserEditComposerProps> = ({ cwd, gateway, sess
           return
         }
 
+        const editor = editorRef.current
+
+        // Dirty edit guard: when the user actually typed something, blur must
+        // not cancel the composer — that would discard their in-flight
+        // edits. Compare against the draft captured immediately before the
+        // first edit; when no edit event occurred, the current hydrated draft
+        // is the clean baseline.
+        const initialDraft = initialDraftRef.current ?? draftRef.current
+
+        if (editor && syncDraftFromEditor(editor) !== initialDraft) {
+          closeTrigger()
+
+          return
+        }
+
         closeTrigger()
         aui.composer().cancel()
       }, 80)
     },
-    [aui, closeTrigger, submitting]
+    [aui, closeTrigger, submitting, syncDraftFromEditor]
   )
 
   const handleKeyDown = (event: KeyboardEvent<HTMLDivElement>) => {

apps/desktop/src/components/assistant-ui/thread/user-message-edit.test.tsx

@@ -8,8 +8,8 @@ import { ExportedMessageRepository } from '@assistant-ui/react'
 // bubbles) is not reproducible in jsdom — see USER_BUBBLE_BASE_CLASS's no-drag
 // carve-out in thread.tsx.
 import { AssistantRuntimeProvider, type ThreadMessage, useExternalStoreRuntime } from '@assistant-ui/react'
-import { fireEvent, render, screen, waitFor } from '@testing-library/react'
-import { describe, expect, it, vi } from 'vitest'
+import { act, cleanup, fireEvent, render, screen, waitFor } from '@testing-library/react'
+import { afterEach, describe, expect, it, vi } from 'vitest'
 
 import { useIncrementalExternalStoreRuntime } from '@/lib/incremental-external-store-runtime'
 
@@ -32,6 +32,10 @@ vi.stubGlobal('CSS', { escape: (str: string) => str })
 
 Element.prototype.scrollTo = function scrollTo() {}
 
+afterEach(() => {
+  cleanup()
+})
+
 function stubOffsetDimension(
   prop: 'offsetHeight' | 'offsetWidth',
   clientProp: 'clientHeight' | 'clientWidth',
@@ -50,6 +54,19 @@ function stubOffsetDimension(
 stubOffsetDimension('offsetWidth', 'clientWidth', 800)
 stubOffsetDimension('offsetHeight', 'clientHeight', 600)
 
+async function moveFocusOutside(editor: HTMLElement) {
+  const outside = window.document.createElement('button')
+  window.document.body.append(outside)
+  editor.focus()
+
+  await act(async () => {
+    outside.focus()
+    await new Promise(resolve => window.setTimeout(resolve, 120))
+  })
+
+  outside.remove()
+}
+
 function userMessage(): ThreadMessage {
   return {
     id: 'user-1',
@@ -128,6 +145,33 @@ describe('click-to-edit user message', () => {
     })
   })
 
+  it('keeps a dirty inline edit open when focus leaves the composer', async () => {
+    const { container } = render(<IncrementalHarness onEdit={async () => {}} />)
+
+    fireEvent.click(await screen.findByRole('button', { name: 'Edit message' }))
+
+    const editor = await screen.findByRole('textbox', { name: 'Edit message' })
+    const editedText = 'edited draft that must not be discarded'
+
+    editor.textContent = editedText
+    fireEvent.input(editor)
+    await moveFocusOutside(editor)
+
+    expect(container.querySelector('[data-slot="aui_edit-composer-root"]')).toBeTruthy()
+    expect((await screen.findByRole('textbox', { name: 'Edit message' })).textContent).toBe(editedText)
+  })
+
+  it('still cancels an untouched inline edit when focus leaves the composer', async () => {
+    const { container } = render(<IncrementalHarness onEdit={async () => {}} />)
+
+    fireEvent.click(await screen.findByRole('button', { name: 'Edit message' }))
+    const editor = await screen.findByRole('textbox', { name: 'Edit message' })
+
+    await moveFocusOutside(editor)
+
+    expect(container.querySelector('[data-slot="aui_edit-composer-root"]')).toBeFalsy()
+  })
+
   it('opens the edit composer with the stock runtime', async () => {
     const { container } = render(<StockHarness onEdit={async () => {}} />)