Windows app mangles extended WSL UNC file links (`\\?\UNC\...` → `/?/UNC/...`)

Summary

In Codex Desktop for Windows, clicking a Markdown file link whose target is a valid extended WSL UNC path opens a blank file preview with "Unable to open file".

The same file opens normally when clicked from the app's file sidebar. Local diagnostics show that the chat-link path is rewritten before the file-open handler receives it.

Environment

• Codex Desktop: 26.707.31428
• Windows 11 x64
• WSL2 workspace

Reproduction

1. Open a workspace stored in WSL, for example:

``text
\\wsl.localhost\<distro>\home\<user>\<repo>
``

1. Confirm that a file opens normally when clicked in the Codex file sidebar.
2. Add a Markdown link targeting the same file with an extended UNC path:

``markdown
[file](<\\?\UNC\wsl.localhost\<distro>\home\<user>\<repo>\<file>.md>)
``

1. Click the link.

Evidence

The original extended UNC path is valid and readable from the Windows host. However, the Codex Desktop log records:

warning [electron-message-handler] Failed to watch open file
errorMessage="Invalid request: AbsolutePathBuf deserialized without a base path"
hostId=local
path=/?/UNC/wsl.localhost/<distro>/home/<user>/<repo>/<file>.md

This shows that the valid path:

\\?\UNC\wsl.localhost\...

is transformed into:

/?/UNC/wsl.localhost/...

before the open-file handler receives it. The transformed value is neither a valid Windows UNC path nor a usable WSL path.

Expected behavior

Chat file links should preserve the extended UNC path or resolve it through the same structured workspace/path context used by the file sidebar.

Related issues

• https://github.com/openai/codex/issues/30565
• https://github.com/openai/codex/issues/29347
• https://github.com/openai/codex/issues/16815
• https://github.com/openai/codex/issues/31983