Ubuntu dock causes Gnome shell to crash

[Bhaskar Chatterjee]

Ubuntu dock is causing the gnome shell to crash especially while opening appfolders and clicking out of the app folders. Same problem was also observed during minimizing and maximizing (by clicking the launcher button).

The entire gnome shell was frozen; none of the key bindings worked - except the only option was to switch to the tty by hitting alt-ctrl-f3 and restart from there.

I have played around with all the options in the settings by installing dash to dock extension (since some settings seems to be shared) including transparency, Auto hide, panel & icon size with all kinds of combinations and I managed to fix this issue by disabling / unchecking the option:
Panel mode:extend to screen edge.

After disabling/Unchecking the option- Panel mode:extend to screen edge; this problem could not be replicated again.

lsb_release -a
No LSB modules are available.
Distributor ID: Ubuntu
Description: Ubuntu Focal Fossa (development branch)
Release: 20.04
Codename: focal

apt-cache policy gnome-shell-extension-ubuntu-dock
gnome-shell-extension-ubuntu-dock:
  Installed: 67ubuntu20.04.3
  Candidate: 67ubuntu20.04.3
  Version table:
 *** 67ubuntu20.04.3 500
        500 http://in.archive.ubuntu.com/ubuntu focal/main amd64 Packages
        500 http://in.archive.ubuntu.com/ubuntu focal/main i386 Packages
        100 /var/lib/dpkg/status

ProblemType: Bug
DistroRelease: Ubuntu 20.04
Package: gnome-shell-extension-ubuntu-dock 67ubuntu20.04.3
ProcVersionSignature: Ubuntu 5.4.0-21.25-generic 5.4.27
Uname: Linux 5.4.0-21-generic x86_64
ApportVersion: 2.20.11-0ubuntu24
Architecture: amd64
CurrentDesktop: ubuntu:GNOME
Date: Wed Apr 8 09:56:27 2020
InstallationDate: Installed on 2020-04-02 (5 days ago)
InstallationMedia: Ubuntu 19.10 "Eoan Ermine" - Release amd64 (20191017)
PackageArchitecture: all
ProcEnviron:
 LANGUAGE=en_IN:en
 PATH=(custom, no user)
 XDG_RUNTIME_DIR=<set>
 LANG=en_IN
 SHELL=/bin/bash
SourcePackage: gnome-shell-extension-ubuntu-dock
UpgradeStatus: No upgrade log present (probably fresh install)

[Daniel van Vugt (vanvugt)]

Thank you for taking the time to report this bug and helping to make Ubuntu better. It sounds like some part of the system has crashed. To help us find the cause of the crash please follow these steps:

1. Look in /var/crash for crash files and if found run:
    ubuntu-bug YOURFILE.crash
Then tell us the ID of the newly-created bug.

2. If step 1 failed then look at https://errors.ubuntu.com/user/ID where ID is the content of file /var/lib/whoopsie/whoopsie-id on the machine. Do you find any links to recent problems on that page? If so then please send the links to us.

3. If step 2 also failed then apply the workaround from bug 994921, reboot, reproduce the crash, and retry step 1.

Please take care to avoid attaching .crash files to bugs as we are unable to process them as file attachments. It would also be a security risk for yourself.

[Bhaskar Chatterjee (bhaskarchatterjee)]

Hi Daniel,

I was unable to perform step 1 even after reproducing the crash. No new crash files were generated (related to this issue) after reproducing the crash in /var/crash.

I logged in to TTY (during the crash) and noticed in htop that one of my CPU core (3) was running at 100% which was utilized by gnome-shell. I found the only way to get my computer to respond was to perform:
Killall -3 gnome-shell or systtemctl poweroff -i or by performing hard reset by holding the power button and and in all these cases the crash files were not being generated.

However, here are some of the links from step-2:

https://errors.ubuntu.com/oops/0547bb36-7952-11ea-991e-fa163e102db1
https://errors.ubuntu.com/oops/e93ee410-78c4-11ea-9917-fa163e102db1
https://errors.ubuntu.com/oops/c0118108-780b-11ea-ab44-fa163e983629
https://errors.ubuntu.com/oops/e0b682b4-772d-11ea-9907-fa163e102db1

[Sebastien Bacher (seb128)]

Could you add your 'journalctl -b 0' after triggering the bug? Looks it could be similar to bug #1867763

[Bhaskar Chatterjee (bhaskarchatterjee)]

Yes.

Please refer to the file in the attachment for 'journalctl -b 0' after the crash was triggered. Output was taken while the system was in frozen condition from TTY.

[Daniel van Vugt (vanvugt)]

Thanks. The only thing possibly related that I can see is this occurred on a couple of occasions:

Apr 08 09:52:37 jays-pc gnome-shell[9871]: JS ERROR: Extension <email address hidden>: TypeError: appIconPrototype._onLeaveEvent is undefined
_init@/<email address hidden>/appIcons.js:1052:9

So in the least it seems you're not using Ubuntu packages for your dock, which makes this bug Invalid. Please uninstall all your extensions (or just delete ~/.local/share/gnome-shell/extensions/) and report a new bug for any further problems you might find.