Windows Desktop: clicking Canvas after generating an image breaks the chat

What version of the Codex App are you using?

Codex Desktop 26.818.5229.0 (Microsoft Store package OpenAI.Codex).

What platform is your computer?

Windows 11 Pro x64, version 10.0.26200 (build 26200).

What issue are you seeing?

After Codex generates an image in a chat, clicking the Canvas button causes the chat UI to break or become unusable. The problem occurs consistently for the reporting user and appears to be tied to the transition from a message containing a newly generated image into Canvas.

No private conversation URL, thread ID, local path, or generated image has been included in this public report.

What steps can reproduce the bug?

1. Open Codex Desktop on Windows.
2. Start or open a chat.
3. Ask Codex to generate an image.
4. Wait for the image generation to finish and for the image to appear in the conversation.
5. Click Canvas.
6. The chat UI breaks / becomes unusable.

The reporting user says this happens every time they follow this sequence.

What is the expected behavior?

Canvas should open normally after an image-generation response, and the existing chat should remain responsive and usable.

Actual behavior

Opening Canvas immediately after generating an image breaks the chat UI.

Additional information

• Reproducibility: reported as consistent (every attempt).
• A search of existing open issues found reports about image-heavy threads freezing, but no exact report for the immediate generate image → click Canvas transition.
• More precise symptoms, screenshots, console logs, or a sanitized thread/feedback ID can be added if maintainers request them.

First reproduce the Windows sequence: generate an image in a chat, wait for it to appear, then click Canvas. No file, test, logs, or entry point is named, so trace the Canvas transition from this reproduction. Done means Canvas opens normally and the existing chat remains responsive after the image-generation response.