Windows Desktop: focus/idle transition causes system-wide cursor jitter

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

26.810.7004.0

What subscription do you have?

ChatGPT Business

What platform is your computer?

Microsoft Windows NT 10.0.26200.0 x64

What issue are you seeing?

ChatGPT Desktop causes continuous system-wide mouse/cursor jitter. The behavior is not confined to the ChatGPT window and makes the desktop unusable.

It is reliably triggered after ChatGPT has been open for about 10–30 seconds, or by switching to another application and then clicking back into Codex. Fully closing ChatGPT is the only repeatable immediate recovery.

This reproduces independently of a particular project or task. It closely matches #33258 and #33074, but reproduces on 26.810.7004.0.

Troubleshooting already attempted: firmware and drivers are current; disabled the Computer Use plugin; changed the per-app GPU preference; reset and restarted ChatGPT . None resolved it. No corresponding Codex Application Error or Application Hang events appeared during focus switching.

What steps can reproduce the bug?

1. Launch ChatGPT Desktop.
2. Wait 10–30 seconds, or switch to another application.
3. Click back into ChatGPT.
4. Observe system-wide pointer jitter/flicker across ChatGPT and other Windows applications.
5. Fully close ChatGPT; the jitter stops immediately.

The focus-switch path reproduces this every time.

What is the expected behavior?

Changing focus to or from ChatGPT should not affect cursor composition or input responsiveness anywhere in Windows.

Additional information

No response

Start by reproducing the issue on Windows NT 10.0.26200.0 with Codex App 26.810.7004.0 using the focus-switch steps in this report. Trace the desktop focus transition and cursor-composition path; done means switching to and from ChatGPT no longer causes system-wide pointer jitter, while the existing recovery and troubleshooting details remain accounted for.