Linux 3.19.7 renderer crash (code 7) + “window is not responding” / black pane while using Agent + Extra High

[Poornateja_M]

Where does the bug appear (feature/product)?

Cursor IDE

Describe the Bug

On Ubuntu 24.04, Cursor freezes while using Agent (sometimes immediately after launch). The window shows “The window is not responding” (Close / Keep Waiting / Reopen). The right side of the window often turns into a solid black void. The app then closes or has to be reopened. This has happened continuously since 5 Sep 2026 and blocks real work.
This is a renderer crash, not a project compile error. main.log from the frozen session:

2026-09-06 12:17:09.958 [error] CodeWindow: renderer process gone (reason: crashed, code: 7) 2026-09-06 12:17:37.393 [error] CodeWindow: detected unresponsive 2026-09-06 12:17:41.969 [error] CodeWindow: renderer process gone (reason: clean-exit, code: ) 2026-09-06 12:18:20.682 [error] CodeWindow: detected unresponsive

Steps to Reproduce

1. Open a large workspace (this one is ~1.9 GB).
2. Open Agent in the Agents Window.
3. Set model effort to Extra High.
4. Start an Agent turn that applies file edits (2-file apply was in progress).
5. Window freezes. Sometimes this also happens at the start of a session before much work is done.

Expected Behavior

Cursor stays responsive while Agent runs and applies edits.

Screenshots / Screen Recordings

Operating System

Linux

Version Information

Version: 3.19.7
Commit: 90de2327392570a5f5f625c656c6749d228e6430
VS Code: 1.128.0
Install: .deb (/usr/share/cursor)
Arch: x64

For AI issues: which model did you use?

grok 4.6 extra high

Additional Information

Yes. Agent work is unusable. This is blocking a company project.

Does this stop you from using Cursor

Yes - Cursor is unusable

[deanrie]

Hey, thanks for the detailed report and logs.

This is a known issue on Linux in Cursor 3.19.7. It started with that build and doesn’t depend on workspace size, model, or the Extra High setting.

First, try updating to the latest Linux release 3.19.13 or newer:

• Fully close Cursor and make sure there are no windows or background processes left.
• Download the latest Linux x64 .deb from Cursor · Download
• Install it, for example: sudo dpkg -i ./cursor_*.deb
• Launch Cursor and check Help → About to confirm it’s 3.19.13 or higher.

If the issue still happens on 3.19.13, there’s a proven workaround: roll back to 3.18.25. That version is stable and not affected by the regression. You can get it from the same download page.

Either way, reply here and let us know if updating fixed it or if you had to roll back. If you see “The window is not responding” again on 3.19.13+ or any renderer crash lines in main.log, share the new version number and those log lines and we’ll dig in.