Extension 'Dev Containers' is required: Agents Window - broken

[mjnowen]

Where does the bug appear (feature/product)?

Cursor IDE

Describe the Bug

I am unable to use the “Agents Window” as I just constantly get this pop-up (see attached image) and when I click “install/reload” the window reloads and the pop-up returns.

Steps to Reproduce

Open the Agents Window, from an already open devcontainer environment running Ubuntu on macOS host.

Screenshots / Screen Recordings

Operating System

MacOS
Linux

Version Information

Version: 3.3.12
VSCode Version: 1.105.1
Commit: 75c0dfd29aecf2cc208dbaf761d5cc459c601aa0
Date: 2026-05-06T03:47:52.249Z
Layout: editor
Build Type: Stable
Release Track: Default
Electron: 39.8.1
Chromium: 142.0.7444.265
Node.js: 22.22.1
V8: 14.2.231.22-electron.0
OS: Darwin arm64 25.4.0

Does this stop you from using Cursor

No - Cursor works, but with this issue

[deanrie]

Hey, this is a known limitation. Dev Containers aren’t supported in the Agents Window in Glass yet. The extension gets filtered on startup, so install and reload loops forever.

Workaround: open a normal window using the “Open Editor Window” command in Glass, or start Cursor in classic mode:

cursor --classic

In classic mode, Dev Containers work as usual.

Dev Containers support in Glass is on our radar, but I can’t share an ETA yet. I’m closing this thread as a duplicate so the discussion stays in one place: Dev container remotes don't work with Glass. That thread also has details and updates.