Missing titlebar buttons (minimize/maximize/close) on Linux Mint Cinnamon X11

[brainexcerpts]

Thanks for the awesome port!

The Claude Desktop window opens and functions normally, but the titlebar decoration buttons (minimize, maximize, close) are completely absent. The window itself is moveable and resizable, but there are no buttons in the top-right corner.

What I tried:

• CLAUDE_MENU_BAR=1 claude-desktop — no effect
• CLAUDE_MENU_BAR=true claude-desktop — no effect
• claude-desktop --ozone-platform=x11 — no effect
• wmctrl -r "Claude" -b add,decorated — no effect

claude-desktop --doctor
Claude Desktop Diagnostics
================================

[PASS] Installed version: 1.3109.0-1.3.32
[PASS] Display server: X11 (DISPLAY=:0)
       Menu bar mode: auto (default, Alt toggles visibility)
[PASS] Electron: v41.2.1 (/usr/lib/claude-desktop/node_modules/electron/dist/electron)
[PASS] Chrome sandbox: permissions OK (/usr/lib/claude-desktop/node_modules/electron/dist/chrome-sandbox)
[PASS] SingletonLock: held by running process (PID 12125)
       MCP config: not found at /home/arkan/.config/Claude/claude_desktop_config.json (OK if not using MCP)
[PASS] Node.js: v20.20.2
       Path: /usr/bin/node
[PASS] Desktop entry: /usr/share/applications/claude-desktop.desktop
[PASS] Disk space: 253804MB free

Cowork Mode
----------------
[PASS] bubblewrap: found
[PASS] KVM: accessible
[PASS] vsock: module loaded
       QEMU: not found
[PASS] socat: found
       virtiofsd: not found
       VM image: not downloaded yet
       Cowork isolation: bubblewrap (namespace sandbox)
[PASS] Log file: 3KB (/home/arkan/.cache/claude-desktop-debian/launcher.log)

A related issue, that probably need its own ticket, is that when you double click on the title bar, content does not resize. So if you start from:

After double click, you'll get:

[github-actions]

I've tracked this down to scripts/frame-fix-wrapper.js. The wrapper sets frame: true on the main window, but uses delete options.titleBarStyle instead of explicitly setting options.titleBarStyle = 'default'. On Cinnamon's Muffin WM, that difference matters. Without an explicit 'default', Electron doesn't send the right X11 MOTIF hints, so Muffin draws resize borders but skips the titlebar buttons.

The upstream main window is created with titleBarStyle: "hidden" (line 505117 in index.js). The wrapper removes that, but "removed" and "set to default" behave differently on this WM.

The fix is straightforward:

// scripts/frame-fix-wrapper.js ~line 116
// Before:
delete options.titleBarStyle;

// After:
options.titleBarStyle = 'default';

There's a secondary issue too. isPopupWindow() checks titleBarStyle === '', which matches nothing in the current source. About/Buddy windows use titleBarStyle: "hiddenInset" with no minWidth, so they slip through and get frame: true applied when they shouldn't. That check should be updated to catch any non-default titleBarStyle on windows without a minWidth.

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This is an automated triage comment. A maintainer will review this issue and may provide further guidance.

Written by Claude Sonnet via Claude Code