gnome-shell crashes with SIGSEGV just after logging "JS ERROR: TypeError: window is null" from _destroyWindow() [windowManager.js:1543:9]

[Daniel van Vugt]

Impact
======
GNOME Shell crashes when it's restarted on Xorg. (There is no option to restart GNOME Shell on Wayland.)

Test Case
=========
Install the update
On the login screen, select your name.
Click the gear button in the lower right and choose Ubuntu on Xorg
Enter your password to finish logging in.
Open the file browser.
Press Alt-F2.
In the dialog, enter 'r'
GNOME Shell should restart without a crash message. Your file browser window should remain open.

What Could Go Wrong
===================
See the master bug for this update LP: #1976381

More Details
============
gnome-shell crashes with SIGSEGV just after logging:

gnome-shell[3117]: JS ERROR: TypeError: window is null
_destroyWindow@resource:///org/gnome/shell/ui/windowManager.js:1543:9
_initializeUI/<@resource:///org/gnome/shell/ui/main.js:260:16

Examples:

https://errors.ubuntu.com/oops/96ee1700-c208-11ec-a3de-fa163ef35206
https://errors.ubuntu.com/oops/e97480f0-c1bc-11ec-a3d8-fa163ef35206
https://errors.ubuntu.com/oops/aa5bf652-d517-11ec-9aa3-fa163e55efd0

Tracking in:

https://errors.ubuntu.com/problem/eb1d2411708c44f1299f717f5a9c19c03cf80470
^^^ this is the second most common gnome-shell crash on errors.ubuntu.com

[Daniel van Vugt (vanvugt)]

Various crash reports as well as the upstream bug all suggest this is Xorg-specific.

[Daniel van Vugt (vanvugt)]

Fix proposed in:
https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/2403

[Daniel van Vugt (vanvugt)]

Fixed upstream in mutter 43, but 42 is coming:
https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/2410

[Launchpad Janitor (janitor)]

This bug was fixed in the package mutter - 42.2-1ubuntu1

---------------
mutter (42.2-1ubuntu1) kinetic; urgency=medium

  * Merge from Debian unstable. Remaining changes:
    - Add triple-buffering patch
    - Add x11-Add-support-for-fractional-scaling-using-Randr.patch:
      + X11: Add support for fractional scaling using Randr
    - Add ubuntu/wayland-data-device-Allow-any-drag-timestamp....patch
      + Allow any drag timestamp as drag start serial
    - Add backends-native-kms-crtc-Don-t-compare-gamma-values-on-un.patch
      + Avoid memory errors when comparing gamma values
    - Add monitor-manager-Ensure-monitors-settings-after-backend-ha.patch
      + Ensure privacy screen settings are applied on startup
    - Add patches from GNOME !2364
      + Fix X11 selection related crash when Xwayland died
    - debian/libmutter-10-0.symbols: Add symbols for triple buffering patch
  * Refresh patches
  * Drop privacy screen settings patch: applied in new release

mutter (42.2-1) unstable; urgency=medium

  * New upstream release (LP: #1976381)
    - Fix crash when restarting GNOME Shell on Xorg (LP: #1969893)

 -- Jeremy Bicha <email address hidden> Wed, 01 Jun 2022 08:08:58 -0400

[Steve Langasek (vorlon)]

Hello Daniel, or anyone else affected,

Accepted mutter into jammy-proposed. The package will build now and be available at https://launchpad.net/ubuntu/+source/mutter/42.2-0ubuntu1 in a few hours, and then in the -proposed repository.

Please help us by testing this new package. See https://wiki.ubuntu.com/Testing/EnableProposed for documentation on how to enable and use -proposed. Your feedback will aid us getting this update out to other Ubuntu users.

If this package fixes the bug for you, please add a comment to this bug, mentioning the version of the package you tested, what testing has been performed on the package and change the tag from verification-needed-jammy to verification-done-jammy. If it does not fix the bug for you, please add a comment stating that, and change the tag to verification-failed-jammy. In either case, without details of your testing we will not be able to proceed.

Further information regarding the verification process can be found at https://wiki.ubuntu.com/QATeam/PerformingSRUVerification . Thank you in advance for helping!

N.B. The updated package will be released to -updates after the bug(s) fixed by this package have been verified and the package has been in -proposed for a minimum of 7 days.

[Jeremy Bícha (jbicha)]

I installed mutter 42.2-0ubuntu1 and completed this restart test case successfully.

[Launchpad Janitor (janitor)]

This bug was fixed in the package mutter - 42.2-0ubuntu1

---------------
mutter (42.2-0ubuntu1) jammy; urgency=medium

  * New upstream release (LP: #1976381)
     - Fix crash when restarting GNOME Shell on Xorg (LP: #1969893)
  * Refresh patches. Drop privacy screen settings patch: applied in new release

 -- Jeremy Bicha <email address hidden> Tue, 07 Jun 2022 14:53:49 -0400

[Łukasz Zemczak (sil2100)]

The verification of the Stable Release Update for mutter has completed successfully and the package is now being released to -updates. Subsequently, the Ubuntu Stable Release Updates Team is being unsubscribed and will not receive messages about this bug report. In the event that you encounter a regression using the package from -updates please report a new bug using ubuntu-bug and tag the bug report regression-update so we can easily find any regressions.