tiling operation triggers assertion in gnome-shell [meta_window_get_workspaces: code should not be reached]

[Eduardo-sanchez-mata]

Ubuntu 24.04 LTS
gnome-shell-extension-ubuntu-tiling-assistant 46-1ubuntu1
gnome-shell 46.0-0ubuntu5.1

I am at a very stock X11 session with a i915 laptop. I move a firefox window from my primary monitor to my secondary monitor and make it full screen.

I am running, I guess, tile(...) in tilingWindowManager.js and I am exactly at

    const workArea = new Rect(window.get_work_area_for_monitor(monitor));

I trigger this:

    jun 06 00:31:53 MY-LAPTOP gnome-shell[3609]: ../../../gobject/gsignal.c:2685: instance '0x5886a5604300' has no handler with id '456691'
    jun 06 00:31:53 MY-LAPTOP gnome-shell[3609]: meta_window_set_stack_position_no_sync: assertion 'window->stack_position >= 0' failed
    jun 06 00:31:53 MY-LAPTOP gnome-shell[3609]: meta_window_set_stack_position_no_sync: assertion 'window->stack_position >= 0' failed
    jun 06 00:31:53 MY-LAPTOP gnome-shell[3609]: **
    jun 06 00:31:53 MY-LAPTOP gnome-shell[3609]: libmutter:ERROR:../src/core/window.c:5444:meta_window_get_workspaces: code should not be reached
    jun 06 00:31:53 MY-LAPTOP gnome-shell[3609]: Bail out! libmutter:ERROR:../src/core/window.c:5444:meta_window_get_workspaces: code should not be reached
    jun 06 00:31:53 MY-LAPTOP gnome-shell[3609]: GNOME Shell crashed with signal 6
    jun 06 00:31:53 MY-LAPTOP gnome-shell[3609]: == Stack trace for context 0x5886994827c0 ==
    jun 06 00:31:53 MY-LAPTOP gnome-shell[3609]: #0 58869954f460 i file:///<email address hidden>/src/extension/tilingWindowManager.js:157 (3b1b8336e>
    jun 06 00:31:53 MY-LAPTOP gnome-shell[3609]: #1 58869954f3a0 i file:///<email address hidden>/src/extension/moveHandler.js:264 (3b1b8319240 @ 495)
    jun 06 00:31:53 MY-LAPTOP gnome-shell[3609]: #2 58869954f318 i file:///<email address hidden>/src/extension/moveHandler.js:233 (3b1b83191f0 @ 48)
    jun 06 00:31:53 MY-LAPTOP gnome-shell[3609]: #3 58869954f288 i resource:///org/gnome/shell/ui/init.js:21 (2cdb70270bf0 @ 48)
    jun 06 00:31:55 MY-LAPTOP polkitd[1385]: Unregistered Authentication Agent for unix-session:2 (system bus name :1.97, object path /org/freedesktop/PolicyKit1/AuthenticationAgent, locale e>
    jun 06 00:31:55 MY-LAPTOP systemd[3137]: <email address hidden>: Main process exited, code=dumped, status=6/ABRT
    jun 06 00:31:55 MY-LAPTOP systemd[3137]: <email address hidden>: Failed with result 'core-dump'.
    jun 06 00:31:55 MY-LAPTOP systemd[3137]: <email address hidden>: Triggering OnFailure= dependencies.
    jun 06 00:31:55 MY-LAPTOP systemd[3137]: <email address hidden>: Consumed 11min 13.038s CPU time.
    jun 06 00:31:55 MY-LAPTOP systemd[3137]: <email address hidden>: Scheduled restart job, restart counter is at 1.
    jun 06 00:31:55 MY-LAPTOP systemd[3137]: Started gnome-session-failed.service - GNOME Session Failed lockdown screen (user).
    jun 06 00:31:55 MY-LAPTOP systemd[3137]: Reached target gnome-session-failed.target - GNOME Session Failed.
    jun 06 00:31:55 MY-LAPTOP systemd[3137]: org.gnome.Shell-disable-extensions.service - Disable GNOME Shell extensions after failure was skipped because of an unmet condition check (Conditi>
    jun 06 00:31:55 MY-LAPTOP systemd[3137]: Starting <email address hidden> - GNOME Shell on X11...
    jun 06 00:31:55 MY-LAPTOP gnome-shell[64176]: Running GNOME Shell (using mutter 46.0) as a X11 window and compositing manager

I get the "Oh No! Something has gone wrong and the system can't recover" screen from gnome-shell. The session is lost. It has already happened to me a handful of times. This time I could find the crash in the journal, it seems to be happening inside tiling-assistant

This seems to be the same as this bug upstream: https://github.com/Leleat/Tiling-Assistant/issues/329

[Launchpad Janitor (janitor)]

Status changed to 'Confirmed' because the bug affects multiple users.

[Daniel van Vugt (vanvugt)]

Looking at src/core/window.c in Mutter makes me think Mutter is more likely to blame. And there is also an upstream bug: https://gitlab.gnome.org/GNOME/mutter/-/issues/3224