diff --git a/src/renderer/src/components/github/GitHubMarkdownComposer.test.tsx b/src/renderer/src/components/github/GitHubMarkdownComposer.test.tsx
new file mode 100644
index 00000000000..dbfca1bc4da
--- /dev/null
+++ b/src/renderer/src/components/github/GitHubMarkdownComposer.test.tsx
@@ -0,0 +1,176 @@
+// @vitest-environment happy-dom
+
+import { act, cleanup, fireEvent, render, waitFor } from '@testing-library/react'
+import { afterEach, beforeEach, describe, expect, it, vi } from 'vitest'
+import { TooltipProvider } from '@/components/ui/tooltip'
+import { GHCommentComposer } from '@/components/github-item-dialog/discuss-item/gh-comment-composer'
+import type { AppState } from '@/store/types'
+import type { GitHubCommentResult, PRComment } from '../../../../shared/github/comment-types'
+import { GitHubMarkdownComposer } from './GitHubMarkdownComposer'
+
+type ComposerStoreState = { settings: Partial<AppState['settings']> }
+
+vi.mock('@/store', () => ({
+  useAppStore: (selector: (state: ComposerStoreState) => unknown) => selector({ settings: {} })
+}))
+vi.mock('@/components/editor/RichMarkdownToolbar', () => ({
+  RichMarkdownToolbar: () => null
+}))
+vi.mock('@/components/editor/RichMarkdownTableControls', () => ({
+  RichMarkdownTableControls: () => null
+}))
+vi.mock('@/components/github/github-markdown-composer-preview-pane', () => ({
+  GitHubMarkdownComposerPreviewPane: () => null
+}))
+vi.mock('sonner', () => ({ toast: { error: vi.fn() } }))
+
+const addIssueComment = vi.fn<typeof window.api.gh.addIssueComment>()
+const comment: PRComment = {
+  id: 29533,
+  author: 'test-author',
+  authorAvatarUrl: '',
+  body: 'Submitted comment',
+  createdAt: '2026-10-23T12:00:00Z',
+  url: ''
+}
+
+beforeEach(() => {
+  addIssueComment.mockReset()
+  vi.stubGlobal('api', { gh: { addIssueComment } })
+})
+afterEach(() => {
+  cleanup()
+  vi.unstubAllGlobals()
+})
+
+function getComposerEditor(container: HTMLElement): HTMLElement {
+  const editor = container.querySelector<HTMLElement>('.tiptap')
+  if (!editor) {
+    throw new Error('Composer editor did not mount')
+  }
+  return editor
+}
+
+async function enterComment(container: HTMLElement): Promise<void> {
+  await waitFor(() => expect(container.querySelector('.tiptap')).not.toBeNull())
+  fireEvent.input(getComposerEditor(container), {
+    target: { innerHTML: '<p>Submitted comment</p>' }
+  })
+}
+
+function renderCommentSubmission() {
+  const onCommentAdded = vi.fn()
+  const view = render(
+    <TooltipProvider>
+      <GHCommentComposer
+        repoPath="/folder-workspace"
+        issueNumber={29521}
+        itemType="issue"
+        onCommentAdded={onCommentAdded}
+      />
+    </TooltipProvider>
+  )
+  return { ...view, onCommentAdded }
+}
+
+describe('GitHubMarkdownComposer submission', () => {
+  it('clears the real submission owner and editor after a successful request', async () => {
+    const request = Promise.withResolvers<GitHubCommentResult>()
+    addIssueComment.mockReturnValue(request.promise)
+    const view = renderCommentSubmission()
+    const send = view.getByRole('button', { name: 'Send comment' })
+    await enterComment(view.container)
+    await waitFor(() => expect(send.hasAttribute('disabled')).toBe(false))
+    fireEvent.click(send)
+    await waitFor(() =>
+      expect(getComposerEditor(view.container).getAttribute('contenteditable')).toBe('false')
+    )
+    expect(send.hasAttribute('disabled')).toBe(true)
+    expect(addIssueComment).toHaveBeenCalledOnce()
+    expect(addIssueComment.mock.calls[0]?.[0].body).toBe('Submitted comment')
+
+    await act(async () => request.resolve({ ok: true, comment }))
+
+    await waitFor(() => {
+      expect(getComposerEditor(view.container).textContent).toBe('')
+      expect(getComposerEditor(view.container).getAttribute('contenteditable')).toBe('true')
+      expect(send.hasAttribute('disabled')).toBe(true)
+    })
+    expect(view.onCommentAdded).toHaveBeenCalledExactlyOnceWith(comment)
+  })
+
+  it.each(['result-error', 'rejection'])(
+    'preserves a failed draft for retry (%s)',
+    async (kind) => {
+      const request = Promise.withResolvers<GitHubCommentResult>()
+      addIssueComment.mockReturnValueOnce(request.promise)
+      const view = renderCommentSubmission()
+      const send = view.getByRole('button', { name: 'Send comment' })
+      await enterComment(view.container)
+      await waitFor(() => expect(send.hasAttribute('disabled')).toBe(false))
+      fireEvent.click(send)
+      await waitFor(() =>
+        expect(getComposerEditor(view.container).getAttribute('contenteditable')).toBe('false')
+      )
+
+      await act(async () => {
+        if (kind === 'rejection') {
+          request.reject(new Error('Request failed'))
+        } else {
+          request.resolve({ ok: false, error: 'Request failed' })
+        }
+      })
+
+      await waitFor(() => {
+        expect(getComposerEditor(view.container).textContent).toBe('Submitted comment')
+        expect(getComposerEditor(view.container).getAttribute('contenteditable')).toBe('true')
+        expect(send.hasAttribute('disabled')).toBe(false)
+      })
+      expect(view.onCommentAdded).not.toHaveBeenCalled()
+      const retry = Promise.withResolvers<GitHubCommentResult>()
+      addIssueComment.mockReturnValueOnce(retry.promise)
+      fireEvent.click(send)
+      await waitFor(() =>
+        expect(getComposerEditor(view.container).getAttribute('contenteditable')).toBe('false')
+      )
+      await act(async () => retry.resolve({ ok: true, comment }))
+      await waitFor(() => {
+        expect(getComposerEditor(view.container).textContent).toBe('')
+        expect(send.hasAttribute('disabled')).toBe(true)
+      })
+      expect(view.onCommentAdded).toHaveBeenCalledExactlyOnceWith(comment)
+    }
+  )
+
+  it('does not report editability changes as draft edits', async () => {
+    const onChange = vi.fn()
+    const props = { value: 'Draft comment', onChange, placeholder: 'Add a comment…' }
+    const view = render(<GitHubMarkdownComposer {...props} />)
+    await waitFor(() => expect(view.container.querySelector('.tiptap')).not.toBeNull())
+    onChange.mockClear()
+
+    view.rerender(<GitHubMarkdownComposer {...props} disabled />)
+    view.rerender(<GitHubMarkdownComposer {...props} disabled={false} />)
+
+    expect(onChange).not.toHaveBeenCalled()
+  })
+
+  it('accepts an external nonempty value while editability changes', async () => {
+    const onChange = vi.fn()
+    const props = { value: 'Original description', onChange, placeholder: 'Description' }
+    const view = render(<GitHubMarkdownComposer {...props} />)
+    await waitFor(() => expect(getComposerEditor(view.container).textContent).toBe(props.value))
+    onChange.mockClear()
+
+    view.rerender(<GitHubMarkdownComposer {...props} value="Updated description" disabled />)
+    await waitFor(() =>
+      expect(getComposerEditor(view.container).textContent).toBe('Updated description')
+    )
+    view.rerender(
+      <GitHubMarkdownComposer {...props} value="Updated description" disabled={false} />
+    )
+
+    expect(getComposerEditor(view.container).getAttribute('contenteditable')).toBe('true')
+    expect(onChange).not.toHaveBeenCalled()
+  })
+})
diff --git a/src/renderer/src/components/github/GitHubMarkdownComposer.tsx b/src/renderer/src/components/github/GitHubMarkdownComposer.tsx
index 52d7906df08..95901079162 100644
--- a/src/renderer/src/components/github/GitHubMarkdownComposer.tsx
+++ b/src/renderer/src/components/github/GitHubMarkdownComposer.tsx
@@ -201,7 +201,7 @@ export function GitHubMarkdownComposer({
       return
     }
     editorRef.current = editor
-    editor.setEditable(!disabled)
+    editor.setEditable(!disabled, false)
   }, [disabled, editor])
 
   useEffect(() => {