Codex OpenAI's extension not working in Cursor IDE 3.15+

Where does the bug appear (feature/product)?

Cursor IDE

Describe the Bug

The Codex OpenAI’s extension ( id: openai.chatgpt, version: 26.814.41407 ) is not working anymore in Cursor IDE in the last minor versions (3.16.x and 3.15.x).

It is working properly in 3.14.x.

The “Open Codex Sidebar” option in the “More Actions …” menu does not open the codex panel anymore. No errors displayed, a click just not open the panel making the Codex extension unusable.

Steps to Reproduce

Just use Cursor 3.15+ with Codex OpenAI’s extension. Don’t know if the issue is limited to Linux OS.

Expected Behavior

The Codex OpenAI’s extension should work properly.

Operating System

Linux

Version Information

Version: 3.16.29
VS Code Extension API: 1.128.0
Commit: 6246455961129c32969845e00aa25d87ae926ec0
Date: 2026-08-18T01:26:26.285Z
Layout: IDE
Build Type: Stable
Release Track: Default
Electron: 40.10.3
Chromium: 144.0.7559.236
Node.js: 24.15.0
V8: 14.4.258.32-electron.0
xterm.js: 6.1.0-beta.291
OS: Linux x64 7.0.0-28-generic

Does this stop you from using Cursor

No - Cursor works, but with this issue

Hi @Marlou Thanks for the post. This is intended behavior rather than something that went wrong in 3.15. The Secondary Side Bar, the right hand panel where Cursor’s Agent tabs live, is reserved for Cursor’s own agent UI, so extensions can’t register a view container there. Codex registers its panel in exactly that spot, so Open Codex Sidebar has nothing to reveal, and that failure gets logged rather than surfaced, which is why the click looks like it does nothing. Your 3.14.x observation is accurate: for about a month a change on our side made that docking possible when it wasn’t meant to be, and 3.15 brought it back in line. It wasn’t anything you configured, there’s no setting that restores it, and it isn’t specific to Linux.

Codex should still work from the left sidebar. It usually lands at the bottom of the Explorer accordion, so drag its section header onto the Activity Bar to give it a top level icon, running View: Reset View Locations then Developer: Reload Window first if it won’t budge. For a side by side layout, Codex: New Codex Agent (a different command from the one you tried) followed by View: Split Editor Right puts it next to your code.