Reproduction steps:
1. Create a new project

Expected results: Project opens successfully
Actual results: Unity Editor crashes

Reproduced with: 6000.0.29f1, 6000.0.31f1, 6000.1.0a8
Not reproduced with: 2021.3.47f1, 2022.3.53f1, 6000.0.28f1

Reproduced on: Ubuntu 24.04 (XFCE), other distributions with Tiling Window Managers
Not reproduced on: Ubuntu 24.04 (Gnome), Windows

First lines of the stack trace from gdb:
#0 0x00005555587b9a43 in Application::HandleEditorFocusChange(bool) ()
#1 0x0000555558ef3952 in PropertyChangeFilter(void*, _GdkEvent*, void*) ()
#2 0x00007ffff5d8e290 in gdk_event_apply_filters (xevent=xevent@entry=0x7fffffffe1a0, event=event@entry=0x55555b6fd260, window=0x55555b662ed0) at ../gtk/gdk/x11/gdkeventsource.c:79
#3 0x00007ffff5d96068 in gdk_event_source_translate_event (event_source=0x55555b688f30, xevent=0x7fffffffe1a0) at ../gtk/gdk/x11/gdkeventsource.c:205
#4 _gdk_x11_display_queue_events (display=0x55555b67c770) at ../gtk/gdk/x11/gdkeventsource.c:341

Notes:
* Last line in the logs is ‘The selected window backend is (null)’
* CQA did not test this on xfce, all information is put together from other user reports