Review Diff crashes with "Thread context is unavailable for non-thread routes" and then shows "No diff available"

What version of the IDE extension are you using?

(ChatGPT/Codex extension version from the Extensions page, e.g. 1.x.x)

What subscription do you have?

ChatGPT Plus

Which IDE are you using?

VS Code 1.xx.x Also reproducible in Cursor (latest version), indicating this is not IDE-specific.

What platform is your computer?

Darwin 24.6.0 arm64 arm

What issue are you seeing?

The Codex Review Diff page consistently fails to load after a task completes.

This issue is reproducible across multiple VS Code-based IDEs (VS Code and Cursor), so it does not appear to be IDE-specific.

When I open the Review Diff page:

1. The page displays "Oops, an error has occurred."
2. Clicking "Try again" changes the page to "No diff available."

The generated response completes successfully, but the Review Diff UI never loads.

Developer Console shows the following error:

Diff error.txt

Error: Thread context is unavailable for non-thread routes

Caused by:
editor-diff-page
React ErrorBoundary

What steps can reproduce the bug?

1. Open a repository in VS Code or Cursor.
2. Start a Codex task that edits one or more files.
3. Wait for the task to finish.
4. Click "Review Diff".
5. Observe "Oops, an error has occurred."
6. Click "Try again".
7. Observe "No diff available".

The issue reproduces consistently.

What is the expected behavior?

Diff should be visible

Additional information

Additional observations:

• Reproduces in both VS Code and Cursor.
• Not related to Git state.
• Not related to the repository.
• Reproduces across different projects.
• Console consistently reports: