gnome-shell crashes every time I unlock my screen

[Shaw Terwilliger]

After a recent "apt upgrade", for about 4 days gnome-shell crashes every time I lock/unlock my screen. Disabling the screen lock lets me run X and Wayland sessions with GNOME indefinitely. Manually locking my screen or letting it lock automatically causes gnome-shell to crash when I try to unlock it. When it crashes, it hangs for a long time without updating the mouse cursor (probably writing the large core dump), then finally dies and the window system restarts and I can log in.

I've disabled all GNOME extensions and tried some other configuration changes but I can't find a work-around except to avoid the lock screen.

Description: Ubuntu Focal Fossa (development branch)
Release: 20.04

gnome-shell:
  Installed: 3.35.91-1ubuntu2
  Candidate: 3.35.91-1ubuntu2
  Version table:
 *** 3.35.91-1ubuntu2 500
        500 http://us.archive.ubuntu.com/ubuntu focal/main amd64 Packages
        100 /var/lib/dpkg/status

ProblemType: Bug
DistroRelease: Ubuntu 20.04
Package: gnome-shell 3.35.91-1ubuntu2
ProcVersionSignature: Ubuntu 5.4.0-14.17-generic 5.4.18
Uname: Linux 5.4.0-14-generic x86_64
ApportVersion: 2.20.11-0ubuntu18
Architecture: amd64
Date: Sat Mar 7 07:30:22 2020
DisplayManager: gdm3
GsettingsChanges:

InstallationDate: Installed on 2018-02-28 (737 days ago)
InstallationMedia: Ubuntu 17.10 "Artful Aardvark" - Release amd64 (20180105.1)
ProcEnviron:
 TERM=xterm-256color
 PATH=(custom, no user)
 LANG=en_US.UTF-8
 SHELL=/bin/zsh
RelatedPackageVersions: mutter-common 3.35.91-1ubuntu1
SourcePackage: gnome-shell
UpgradeStatus: Upgraded to focal on 2019-12-13 (84 days ago)

[Shaw Terwilliger (sterwill)]

apport doesn't ever successfully upload the full crash dump. It always gets an HTTP 503 at the end, which I figure is the server timing out from the 1 GB core dump upload. I can provide a backtrace, thread dump, or other info from the dump if it would be helpful.

[Sebastien Bacher (seb128)]

Thank you for your bug report, do you have animations disabled? There is a known bug in that configuration that is going to be fixed in the next update

[Shaw Terwilliger (sterwill)]

Yes, I do have animations disabled. I'll re-enable them and see if that works around the crashes.

[Shaw Terwilliger (sterwill)]

Enabling animations seems to work around the bug. I can lock and unlock my screen manually without crashing gnome-shell. Thanks!

[Sebastien Bacher (seb128)]

the upstream git fix is https://gitlab.gnome.org/GNOME/gnome-shell/-/commit/3633e1fe