GTK crashes when unplugging external monitor

Steps to reproduce

1. Connect an external monitor to a laptop
2. Run gtk4-demo
3. Unplug the external monitor

Version information

GTK 4.12.1
Windows 11 Pro

Also confirmed by another user on Windows 10. Does not happen in GTK 3.

Warnings

None

Backtrace

I don't currently have the necessary tools to get a proper stack trace, but I can look into obtaining one if others aren't able to reproduce the crash.