After upgrade to Cursor 3.15.6 Codex extension disappeared from UI, Cmd+Shift+P → Codex: Open Codex Sidebar does not work as well. Cmd+Shift+P → Codex: New Codex Agent works, but it opens non-multiplexed version of Codex extension UI, much less convenient compared to multiplexed sidebar.
All worked well on 3.14.x before the upgrade. I use Linux / XFCE.
Hi. Same here on Macbook , I upgraded to 3.15.6 and Codex tab now under Explorer and I cannot drag it in to the Agents pane on the right side. Any suggestions?
Before upgarde. My layout was: Left side - Explorer, middle side - my code and right side - Codex. Now on 3.15.6 codex is disappeared from the right side and moved under explorer. How to return my layout?
I encountered the same problem, with the same version.
I have the same problem, from the latest update: Version: 3.15.6 (system setup)
VS Code Extension API: 1.128.0
Commit: a1f686545fd0ce8917bbd2449f733551a9bce420
Date: 2026-08-06T01:41:03.876Z
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: Windows_NT x64 10.0.26200
It worked yesterday.
EDIT: Confirmed, downgrading to 3.14.27 made it work again.
Same problem here, version 3.15.6. Codex disapeared, again. Would be nice to be careful about this .. especially when it already happened once.
Solution: roll back to version 3.14.27
Is there any risk to lose parameters or anything when downgrading ? What’s the easiest way to do it ?
That’s just annoying tbh and it should not even happens twice.
Annoying, It’s downright annoying! I even wrote about it in this thread: Aren't you tired of breaking the UI and UX in a working tool? - #2 by system
I noticed a problem after updating and downgraded by downloading the 3.14 image from here Cursor · Download and simply installing it over it. MacOS. Nothing was lost, and the Codex was back where it was.
who is the person respsonsible for making unneccesary changes to the codex UI and removing the normal Codex extension from the top of the IDE to the bottom where you can no longer access your chats? Have a long talk with them, this is completely absurd. You did this a couple months ago and i had to downgrade for weeks because of this incomptenece.
For a paid product to do something like this intentionally, that’s just unacceptable. I understand that Cursor’s own models and the chat view are the selling point, but crippling the UI and UX by removing the second sidebar is not the way to do it. Please restore the second sidebar, I can’t work in Cursor anymore because of this change.
macOS — Cursor 3.15.6
I have the same issue after updating to Cursor 3.15.6.
Before the update, I could position the OpenAI Codex extension as a tab alongside my Cursor agent/chat tabs. After updating to 3.15.6, Codex is stuck in a separate editor area and I can no longer move it back.
I have tried:
View: Move Editor into Right GroupNone of these work.
Expected behavior: Codex should be movable into the same tab group where my Cursor tabs are located, as it was before the 3.15.6 update.
Actual behavior: Codex remains in its own area and cannot be moved into that tab group.
OS: macOS
Cursor version: 3.15.6
This worked correctly for me before upgrading to 3.15.6.
Edit: Solution here (Cursor 3.15.6: Codex can no longer be moved into the Agent tab group - #11 by ianmoone163)
I’m on latest version (3.15.6) in win11. The extension is nowhere to be found not in left nor right panel. I’m downgrading now to previous version and disable auto update.
Runtime error show:
Yep - OP here and I report the same. Upgrade to 3.15.6 has re-broken this issue. New bugs are bad enough , but repeatedly breaking the same thing is fairly embarrassing.
My laptop now has update corporately managed so reinstalling a specific version isn’t a simple solution for me.
Timeline on a fix please?
Same issue on Cursor 3.16.17 on Mac
Hey, thanks for the report. To clarify what’s happening, this is an intentional change, not a regression. The Secondary Side Bar (the right panel where Cursor Agent tabs live) is reserved for Cursor’s own agent UI, and third-party extensions can no longer register their panel there. For about a month, a change on our side accidentally allowed this again in 3.14.x, which is why you could keep Codex on the right. In 3.15.6 the behavior returned to what was intended. So in 3.16.17 it’s the same as well, thanks to @ClaudioTrenca for confirming. The screenshots with the missing panel and the runtime error are exactly this case.
What you can do right now:
View: Reset View Locations, then Developer: Reload Window. Dragging sometimes doesn’t work on the first try.Codex: New Codex Agent in the Command Palette, then View: Split Editor Right or drag the tab to the right edge of the editor. It’ll sit next to your code as a separate editor group.What to avoid: don’t manually drag the Codex view into the Secondary Side Bar. It renders empty and doesn’t roll back correctly.
Full explanation and community workarounds are in this thread: Cursor 3.15.6: Codex can no longer be moved into the Agent tab group - #8 by kevinn
I get that the old layout with all AI tools in one panel was more convenient. This is a common request, and I’ve passed your feedback to the team about bringing back or adding an optional way to dock extensions in the Secondary Side Bar. I can’t promise it’ll return, but I’ll post an update if there’s news.
## Workaround: Make Codex show as a primary Activity Bar view in Cursor
I had an issue where the OpenAI Codex extension in Cursor would not pin like Claude Code. Instead of showing as its own Activity Bar item, Codex appeared as a collapsible section inside Explorer.
### Environment
- Cursor: 3.16.29
- Extension: `[email protected]`
- macOS
### Root Cause
The Codex extension manifest contributes Codex conditionally:
- Primary Activity Bar only when `chatgpt.doesNotSupportSecondarySidebar`
- Secondary sidebar when `!chatgpt.doesNotSupportSecondarySidebar`
In Cursor, this can make Codex land in the wrong place or be remembered as hidden/moved in workspace state.
### Fix / Workaround
Quit Cursor fully first.
Edit:
```bash
~/.cursor/extensions/openai.chatgpt-26.814.41407-darwin-arm64/package.json
Change the Codex viewsContainers / views section so Codex is always contributed to the primary Activity Bar.
Before, it had conditional when clauses and a secondarySidebar container.
After:
"viewsContainers": {
"activitybar": [
{
"id": "codexViewContainer",
"title": "Codex",
"icon": "resources/blossom-white.svg"
}
]
},
"views": {
"codexViewContainer": [
{
"id": "chatgpt.sidebarView",
"type": "webview",
"name": "Codex"
}
]
}
Optional but helpful in Cursor settings:
"chatgpt.openOnStartup": true
Then reopen Cursor and run:
View: Reset View LocationsCodex: Open Codex SidebarThis is a local unsupported workaround. Updating the Codex extension may overwrite package.json, so the patch may need to be reapplied after extension updates.
I did not have and do not want Codex in the right panel. It was always in the left panel for me which is what I want to restore.
Your steps don’t work, it can’t be dragged out of Explorer no matter how many times I try because we still have this same console error as when the bug was first raised.
WARN [openai.chatgpt]: View container ‘codexSecondaryViewContainer’ does not exist and all views registered to it will be added to ‘Explorer’.
It’s broken.