Linux/Wayland: dragging the custom title bar crashes yaak-cef with X_QueryPointer BadWindow

Description

Dragging the Yaak window using its title bar immediately terminates the application on GNOME Wayland.

This is consistently reproducible. Moving the same window through GNOME works correctly:

• Super + left-drag works
• Alt + F7 works

Steps to reproduce

1. Install the official yaak-cef_2026.5.0_amd64.deb.
2. Log into a GNOME Wayland session.
3. Launch Yaak normally.
4. Drag the window using Yaak’s title bar.

Expected behavior

The window moves normally.

Actual behavior

Yaak exits immediately.

The journal records:

X Error of failed request:  BadWindow (invalid Window parameter)
  Major opcode of failed request:  38 (X_QueryPointer)
  Resource id in failed request:  0x1
  Serial number of failed request:  7
  Current serial number in output stream:  7

I observed this same error five times.

Before the failure, Yaak also logs:

Tried to initialize the wayland data control protocol clipboard, but failed.
Falling back to the X11 clipboard protocol.

The CEF process logs:

'--ozone-platform=wayland' is not compatible with Vulkan.
Consider switching to '--ozone-platform=x11' or disabling Vulkan

X11 test

Launching with:

GDK_BACKEND=x11 yaak-cef --ozone-platform=x11

prevents the crash, but dragging the title bar becomes a no-op—the window does not move.

GNOME-managed window movement continues to work with both Super + drag and Alt + F7.

Environment

• Yaak: 2026.5.0 amd64
• Package: official yaak-cef_2026.5.0_amd64.deb
• OS: Ubuntu 26.04 LTS
• Kernel: 7.0.0-29-generic
• Desktop: GNOME Shell 50.1
• Session: Wayland
• GPU: NVIDIA GeForce RTX 3090 Ti
• Driver: nvidia-driver-595-open 595.84-0ubuntu0.26.04.1
• Displays: two 2560×1440 monitors arranged horizontally
• Primary display: right monitor
• Scale: 100% on both displays