### Preflight Checklist - [x] I have searched [existing issues](https://github.com/anthropics/claude-code/issues?q=is%3Aissue%20state%3Aopen%20label%3Abug) and this hasn't been reported yet - [x] This is a single bug report (please file separate reports for different bugs) - [x] I am using the latest version of Claude Code ### What's Wrong? On Linux Mint Cinnamon (X11), opening the window menu from the Claude Desktop custom title bar (right-click on the top bar near the window controls) leave

[BUG] Claude Desktop (Linux/Cinnamon X11): window menu from custom title bar gets stuck, desktop appears frozen (pushModal: begin_modal failed)

Status Open

Maintainer reply None cached

Workaround ✓ Mentioned in description ↑

Activity 0 comments · opened Sep 25, 2026

Preflight Checklist

[x] I have searched existing issues and this hasn't been reported yet
[x] This is a single bug report (please file separate reports for different bugs)
[x] I am using the latest version of Claude Code

What's Wrong?

On Linux Mint Cinnamon (X11), opening the window menu from the Claude Desktop custom title bar (right-click on the top bar near the window controls) leaves the Cinnamon window menu (Minimize / Unmaximize / Move / Resize / Always on Top / … / Close) stuck on screen. The menu cannot be clicked or dismissed with Esc (also tried sending Esc via xdotool), and the rest of the desktop stops responding to mouse input, so the screen appears locked up. The only recovery is restarting Cinnamon (Ctrl+Alt+Esc).

Happened in at least two separate sessions (Sep 22 and Sep 24, 2026).

Likely cause: the Claude window is frameless (_MOTIF_WM_HINTS = 0x2, 0x0, 0x0, 0x0, 0x0, no WM decorations) and draws its own title bar. When the window menu is requested from that draggable region, the app appears to still hold the X pointer/keyboard grab from the button press, so Muffin can't acquire its modal grab (begin_modal fails) but shows the menu anyway, and it can't receive input. For comparison, Firefox, Nemo and Terminator on the same system use normal WM decorations.

What Should Happen?

The window menu should either work normally (clickable, dismissable with Esc) or not be shown. The desktop should never be left unresponsive.

Error Messages/Logs

From ~/.xsession-errors (Cinnamon), each time it happens:


Gjs-Message: 19:00:15.777: JS LOG: pushModal: invocation of begin_modal failed
Gjs-Message: 19:00:18.818: JS LOG: pushModal: invocation of begin_modal failed


Previous session:

Gjs-Message: 15:57:30.121: JS LOG: pushModal: invocation of begin_modal failed
Gjs-Message: 15:57:30.411: JS LOG: pushModal: invocation of begin_modal failed
Gjs-Message: 15:57:31.593: JS LOG: pushModal: invocation of begin_modal failed

Steps to Reproduce

Linux Mint 22.3 Cinnamon, X11 session.
Open Claude Desktop (official apt package).
Right-click the top bar area of the Claude window near the minimize/maximize/close buttons.
The Cinnamon window menu appears and gets stuck: clicks and Esc do nothing, and the desktop looks frozen.
Recover with Ctrl+Alt+Esc (restart Cinnamon); open windows are kept.

Claude Model

None

Is this a regression?

I don't know

Last Working Version

_No response_

Claude Code Version

Claude Desktop 2.7032.0 (Linux, official apt repo downloads.claude.ai)

Platform

Anthropic API

Operating System

Ubuntu/Debian Linux

Terminal/Shell

Other

Additional Information

Environment:

Claude Desktop: 2.7032.0 (official apt repo, downloads.claude.ai)
OS: Linux Mint 22.3 "Zena" (Ubuntu 24.04 base), Cinnamon edition
Cinnamon 6.6.9, Muffin 6.6.3
Session: X11 (Xorg)
Kernel: 6.8.0-142-generic
GPU: NVIDIA GeForce GTX 1050 Ti, driver 580.178.04

Note: this is the Claude Desktop app, not the Claude Code CLI. Filing here since Linux Desktop app bugs are tracked in this repo.

Workaround: avoid right-clicking the Claude title bar; if stuck, Ctrl+Alt+Esc restarts Cinnamon.

View original on GitHub ↗