I am experiencing the same issue. It appears to be related to losing focus on the Agents tab once it has been separated.
To test I created a blank folder, and opened it in Cursor. I clicked the More actions icon in the “Agents” sidebar, chose “Open tab as editor“, then dragged the Chat tab to my desktop.
Initially it will work as intended but as soon as you focus on the IDE window and then return to the Chat window the bug will appear.
Screenshots / Screen Recordings
Operating System
macOS Tahoe
Version Information
Version: 2.6.21
VSCode Version: 1.105.1
Commit: fea2f546c979a0a4ad1deab23552a43568807590
Date: 2026-03-21T22:09:10.098Z
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 25.2.0