Codex sidebar fails with "couldn't load its resources", webview font blocked by CSP (font-src)
__Environment__
- Extension: openai.chatgpt version 26.803.41515
- Context: Remote-SSH (ssh-remote+server)
- VS Code server commit: df53daabb18cd157bdb08c7f01c34df936cf12f4
- OS: macOS client, Linux remote (x86_64)
__What happened__
The Codex sidebar shows "Codex could not start / The extension couldn't load its resources." The extension host activates openai.chatgpt successfully (confirmed in the remote exthost log, no crash, no exception during activation). The failure happens in the webview, not during extension activation.
Devtools console shows:
Loading the font 'data:font/woff2;base64,...' violates the following
Content Security Policy directive:
"font-src 'self' https://*.vscode-cdn.net". The action has been blocked.immediately followed by:notificationsAlerts.ts:42 Codex couldn't load its resources.
The webview appears to be requesting a font as a data: URI, which the webview's CSP (font-src 'self' https://*.vscode-cdn.net) does not permit. The failed font load appears to trigger the "couldn't load its resources" notification.
__Steps to reproduce__
- Connect to a remote host via Remote-SSH.
- Open the Codex sidebar.
- Observe the "couldn't load its resources" error, then check devtools console for the CSP violation above.
__Expected__
Webview loads normally, or at minimum doesn't ship a resource reference that its own CSP blocks.
__Workaround__
Installing an earlier version of the extension resolves it.
4 Comments
Potential duplicates detected. Please review them and close your issue if it is a duplicate.
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I can independently reproduce this issue in a Linux server environment as well.
When using the Codex VS Code extension against the Linux server, opening the Codex sidebar results in the same startup failure:
This appears to be the same failure described here and in #37458, so it does not seem to be limited to Windows/local environments.
I first noticed the issue when working on the Linux server.
Additional A/B result
Downgrading the Codex VS Code extension resolves the problem immediately. After rolling back to an earlier extension version, the Codex sidebar starts normally again in the same Linux server environment.
This makes a server configuration problem less likely and suggests a regression in the newer extension release.
I can provide the exact VS Code version, affected/working extension versions, remote environment details, and relevant logs if they would help narrow down the cause.
Thanks for reporting this issue. We're tracking the related startup failure in #37458 and will provide updates there.
The startup watchdog fix has shipped. Please see the release announcement in #37458 for the stable and pre-release builds, platform availability, and guidance for any remaining loading issues.