[macOS][Computer History] Chinese IME candidate windows remain as draggable overlays after punctuation

What version of the Codex App are you using (From “About Codex” dialog)?

26.825.51511 (build 7377)

What subscription do you have?

ChatGPT Pro

What platform is your computer?

Darwin 25.5.0 arm64 arm (macOS 26.5, build 25F71, Apple M4)

What issue are you seeing?

When Computer History is running, the macOS built-in Traditional Chinese Quick/Sucheng IME can leave its candidate bar behind as a real, draggable, always-visible window.

The trigger is pressing punctuation (for example ;, ', /, comma, or period) while the candidate list is still open. The character and punctuation are committed, but the old candidate bar does not close. Repeating this accumulates multiple stale candidate bars at previous caret positions. They remain above other applications and can be dragged individually.

This is not framebuffer/GPU ghosting. A live WindowServer inspection captured the stale window as:

• owner: ChatGPT
• layer: 20
• size: 397 x 28
• alpha: 1.0
• on-screen and shared
• no title

There were no matching ChatGPT, WindowServer, or input-method crash reports.

A controlled A/B test strongly isolates Computer History as the trigger:

1. Pause Computer History and reset the TYIM candidate state.
2. Confirm the candidate-like window count is 0.
3. Repeat the exact Quick/Sucheng candidate + punctuation action multiple times: no stale windows appear.
4. Resume Computer History; recorder status reports running.
5. Repeat the same action: one ChatGPT-owned 397 x 28 layer-20 candidate window immediately remains.
6. Pause Computer History and reset TYIM again: the window count returns to 0.

Quitting ChatGPT also clears all stale panels, but restarting the whole app repeatedly is disruptive.

What steps can reproduce the bug?

1. On macOS, enable Computer History and confirm collection is running.
2. Select the built-in Traditional Chinese Quick/Sucheng input source (com.apple.inputmethod.TYIM.Sucheng).
3. Focus the ChatGPT/Codex message composer.
4. Type a Quick/Sucheng code so the horizontal candidate list appears.
5. While the candidate list is open, press punctuation such as ;, ', /, comma, or period.
6. Observe that the text is committed but the candidate list remains as a draggable overlay.
7. Repeat at different caret positions; multiple stale candidate windows accumulate.
8. Switch to another application; the stale candidate windows remain visible above it.

Control: pause Computer History, clear the existing candidate state, and repeat the same steps. The issue no longer reproduces. Resume Computer History and it reproduces again.

What is the expected behavior?

Pressing punctuation while an IME candidate list is open should commit the composition and close the candidate window. Computer History must not change IME composition or candidate-window lifecycle behavior. No candidate overlays should remain after focus changes or after the composition is committed.

Additional information

• App: ChatGPT powered by Codex, version 26.825.51511 (build 7377)
• Bundled Chromium framework: 151.0.7922.174
• macOS 26.5 (25F71), Apple M4
• Input method: Apple Traditional Chinese Quick/Sucheng
• Displays: built-in Retina display plus an external 1080p display
• The symptom began after the app updated from build 7119 to build 7377 and Computer History was enabled on September 1, 2026.
• Native TextEdit correctly dismissed its own candidate panel in a control test.
• Temporary workaround: pause Computer History. Existing stale panels can be cleared without restarting ChatGPT by sending TERM to TYIM_Extension.
• No model, prompt, token usage, or session ID is involved.
• Duplicate searches for "Computer History" IME candidate macOS and "Computer History" "Chinese input" returned no results.
• Adjacent reports: https://github.com/openai/codex/issues/15487 and https://github.com/electron/electron/issues/51557

Screenshots are intentionally not attached because the available captures include unrelated private application content. A redacted recording or logs can be provided if needed.

No source file or test is named. Start by reproducing the issue with Computer History running and the built-in Traditional Chinese Quick/Sucheng input source, then inspect the macOS text-input and candidate-window handling associated with Computer History. Done means punctuation commits the composition and no stale draggable overlays remain, including after focus changes.