VS Code extension: full Review diff page crashes while inline diff works

[Scheronimus]

What version of the IDE extension are you using?

Visual Studio Code 1.130.0, x64

What subscription do you have?

pro

Which IDE are you using?

VS Code

What platform is your computer?

Windows 10 Home, x64

What issue are you seeing?

The full Codex Review/diff page displays:

Oops, an error has occurred

The inline diff card inside the conversation renders the same change correctly.
VS Code Source Control and git diff also work correctly.

What steps can reproduce the bug?

1. Open a valid Git repository in VS Code.
2. Make a small uncommitted text change.
3. Confirm that git diff displays the change.
4. Open the Codex full Review/diff page.
5. The Review page crashes and displays “Oops, an error has occurred.”
6. The inline “Review changes” card continues to render correctly.

What is the expected behavior?

The full Review page displays the repository diff.

Additional information

Actual result

The full Review page hits an error boundary. Only the inline diff works.

Troubleshooting already attempted

• Initialized and validated the Git repository.
• Confirmed git diff works.
• Reloaded the VS Code window.
• Restarted VS Code.
• Disabled and re-enabled the extension.
• Completely uninstalled and reinstalled the extension.
• Tested after creating a fresh filesystem change.
• The failure persists.

Relevant log entry

At 2026-07-25 17:54:05.328:

error boundary ... editor-diff-page-DVdvmt2c.js ... name=AppRoutes

The stack trace points into:

openai.chatgpt-26.721.41059-win32-x64/webview/assets/editor-diff-page-DVdvmt2c.js

Authentication succeeds and the Git repository watcher starts normally before the crash.

Additional observations

• The inline diff renderer works.
• VS Code native Source Control diff works.
• The repository has a valid initial commit and a small uncommitted README change.
• The problem appears isolated to the full editor-diff-page webview route.

[github-actions]

Potential duplicates detected. Please review them and close your issue if it is a duplicate.

• Issues to open Codex Diff files. #35250
• [VS Code] Codex Diff editor tab always crashes with "Thread context is unavailable for non-thread routes" #35076
• Codex Diff crashes with “Oops, an error has occurred” in VS Code on macOS #35058
• Codex not showing diff #35156
• Codex plugin for Antigravity IDE stopped showing diff #35285

Powered by Codex Action

[Scheronimus]

plug-in Version :
26.721.41059

[ThinkWithPbody]

I can reproduce this on Windows 10 with VS Code connected to WSL2.

Additional observations:

• The repository is stored on the WSL ext4 filesystem, not under /mnt/c.
• ~/.codex is stored under the WSL home directory on ext4.
• A fresh Codex thread and fresh file changes behave the same way.
• Hovering over a changed file successfully renders the diff preview.
• Clicking the changed file to open the persistent/full diff view produces “Oops, an error has occurred.”
• VS Code Source Control and git diff work normally.
• Restarting the computer and VS Code did not resolve it.
• The Codex extension is on the latest stable release.

This appears isolated to the click-open/full diff UI rather than Git, WSL filesystem access, or diff generation.

[naltang]

Additional confirmed reproduction under VS Code Remote - WSL2:

• Codex VS Code extension: 26.721.41059 (Linux x64 remote extension)
• VS Code: 1.131.0
• WSL2 kernel: 6.18.33.2-microsoft-standard-WSL2, x86_64
• Repository has an ordinary pending text diff; git status, git diff, and VS Code Source Control all work normally.
• Clicking Review opens the full diff page and displays: Oops, an error has occurred.
• Developer: Reload Window followed by clicking Review reproduces the same failure.

The fresh extension-host log records these consecutive events:

• 2026-07-30 00:04:47.820: fs/readFile fails with No such file or directory (os error 2).
• 2026-07-30 00:04:49.056: the React error boundary fires in editor-diff-page-DVdvmt2c.js.

This appears to be the same regression and confirms it is reproducible in a Remote - WSL environment, not only a native Windows extension host.

[joesnyde]

Additional native Windows reproduction with a confirmed rollback workaround:

• Platform: native Windows (Microsoft Windows NT 10.0.26200.0), VS Code x64
• VS Code: 1.131.0
• Broken Codex VS Code extension: openai.chatgpt@26.721.41059
• Working rollback version: openai.chatgpt@26.609.30741
• Configured model: gpt-5.6-sol, model_reasoning_effort = "medium"

Observed behavior:

1. With 26.721.41059, clicking Codex Diff / full Review page shows Oops, an error has occurred.
2. git diff, git diff --check, and VS Code Source Control all work normally.
3. Reproduces with a normal tracked-file text edit; it also reproduced when the session contained a newly added Markdown test file.
4. Reinstalling / rolling back to 26.609.30741 and pinning openai.chatgpt against auto-update makes Codex Diff work again.
5. Re-upgrading to 26.721.41059 to enable the newer model path caused the Codex Diff error to return; running the rollback script restored Codex Diff again.

Relevant sanitized log signature from Codex.log on the broken build:

Request failed ... method=fs/readFile ... "The system cannot find the path specified. (os error 3)"
error boundary ... editor-diff-page-DVdvmt2c.js ... name=AppRoutes

This looks like the same full diff / Review page regression, and the A/B result suggests it was introduced after 26.609.30741 and is present in 26.721.41059 on native Windows