Dragging the top activities/time bar freezes GNOME completely (Xorg session)

[Connor Nolan]

If you use a touchscreen and drag a finger down on the very top bar (with the time and the former activities button), GNOME will completely freeze.

The mouse cursor will be locked in the "drag" state. All keyboard input (including Alt-F2) will be ignored. The only way to escape this state is to switch into a virtual console and kill the current program.

ProblemType: Bug
DistroRelease: Ubuntu 23.10
Package: gnome-shell 45.0-1ubuntu1
ProcVersionSignature: Ubuntu 6.5.0-5.5-generic 6.5.0
Uname: Linux 6.5.0-5-generic x86_64
NonfreeKernelModules: nvidia_modeset nvidia
ApportVersion: 2.27.0-0ubuntu2
Architecture: amd64
CasperMD5CheckResult: pass
CurrentDesktop: ubuntu:GNOME
Date: Mon Sep 25 12:33:44 2023
DisplayManager: gdm3
InstallationDate: Installed on 2023-08-02 (55 days ago)
InstallationMedia: Ubuntu 23.04 "Lunar Lobster" - Release amd64 (20230418)
ProcEnviron:
 LANG=en_US.UTF-8
 PATH=(custom, no user)
 SHELL=/bin/bash
 TERM=xterm-256color
 XDG_RUNTIME_DIR=<set>
RelatedPackageVersions: mutter-common 45.0-2ubuntu1
SourcePackage: gnome-shell
UpgradeStatus: Upgraded to mantic on 2023-09-23 (2 days ago)

[Daniel van Vugt (vanvugt)]

Next time the problem happens please switch to a virtual console and run:

  journalctl -b0 > journal.txt

and attach the resulting text file here.

[Connor Nolan (thebrokenrail)]

The issue's really consistent and easy to reproduce thankfully.

[Daniel van Vugt (vanvugt)]

When you say the workaround is to "kill the current program" do you mean the foreground app or the shell?

[Connor Nolan (thebrokenrail)]

The foreground app.

[Connor Nolan (thebrokenrail)]

By running "(journalctl -f > journal.txt &) && (nautilus &) && sleep 10 && killall nautilus && sleep 1 && killall journalctl", I was able to acquire only the log entries that occurred while reproducing the bug.

Oct 02 11:12:33 user-83BV systemd[1701]: Started tracker-extract-3.service - Tracker metadata extractor.
Oct 02 11:12:42 user-83BV dbus-daemon[1774]: [session uid=1000 pid=1774] Activating service name='org.gnome.Nautilus' requested by ':1.41' (uid=1000 pid=2293 comm="/usr/bin/gnome-shell" label="unconfined")
Oct 02 11:12:42 user-83BV nautilus[35524]: Connecting to org.freedesktop.Tracker3.Miner.Files
Oct 02 11:12:42 user-83BV dbus-daemon[1774]: [session uid=1000 pid=1774] Successfully activated service 'org.gnome.Nautilus'
Oct 02 11:12:42 user-83BV gnome-shell[2293]: Window manager warning: Buggy client sent a _NET_ACTIVE_WINDOW message with a timestamp of 0 for 0x2e00004
Oct 02 11:12:42 user-83BV gnome-shell[2293]: Meta.Rectangle is deprecated, use Mtk.Rectangle instead
Oct 02 11:12:43 user-83BV gnome-shell[2293]: Can't update stage views actor <unnamed>[<MetaWindowActorX11>:0x55f32df50d10] is on because it needs an allocation.
Oct 02 11:12:43 user-83BV gnome-shell[2293]: Can't update stage views actor <unnamed>[<MetaSurfaceActorX11>:0x55f32d9e56d0] is on because it needs an allocation.
Oct 02 11:12:45 user-83BV wpa_supplicant[1164]: wlp0s20f3: PMKSA-CACHE-ADDED 9c:1c:12:04:5a:d4 0
Oct 02 11:12:46 user-83BV gnome-shell[2293]: Meta.Rectangle is deprecated, use Mtk.Rectangle instead
Oct 02 11:12:52 user-83BV gnome-shell[2293]: Window manager warning: Buggy client sent a _NET_ACTIVE_WINDOW message with a timestamp of 0 for 0x2e00112
Oct 02 11:12:52 user-83BV gnome-shell[2293]: Meta.Rectangle is deprecated, use Mtk.Rectangle instead
Oct 02 11:12:53 user-83BV gnome-shell[2293]: Can't update stage views actor <unnamed>[<MetaWindowActorX11>:0x55f33221e540] is on because it needs an allocation.
Oct 02 11:12:53 user-83BV gnome-shell[2293]: Can't update stage views actor <unnamed>[<MetaSurfaceActorX11>:0x55f32ff14c70] is on because it needs an allocation.
Oct 02 11:12:55 user-83BV dbus-daemon[1774]: [session uid=1000 pid=1774] Activating via systemd: service name='org.freedesktop.Tracker3.Miner.Extract' unit='tracker-extract-3.service' requested by ':1.83' (uid=1000 pid=3211 comm="/usr/libexec/tracker-miner-fs-3" label="unconfined")
Oct 02 11:12:55 user-83BV systemd[1701]: Starting tracker-extract-3.service - Tracker metadata extractor...
Oct 02 11:12:55 user-83BV dbus-daemon[1774]: [session uid=1000 pid=1774] Successfully activated service 'org.freedesktop.Tracker3.Miner.Extract'
Oct 02 11:12:55 user-83BV systemd[1701]: Started tracker-extract-3.service - Tracker metadata extractor.
Oct 02 11:13:02 user-83BV gnome-shell[2293]: Meta.Rectangle is deprecated, use Mtk.Rectangle instead

[Connor Nolan (thebrokenrail)]

This also happens with non-GTK applications like xclock:

Oct 02 11:22:27 user-83BV gnome-shell[2293]: Meta.Rectangle is deprecated, use Mtk.Rectangle instead
Oct 02 11:22:27 user-83BV gnome-shell[2293]: Meta.Rectangle is deprecated, use Mtk.Rectangle instead
Oct 02 11:22:27 user-83BV gnome-shell[2293]: Meta.Rectangle is deprecated, use Mtk.Rectangle instead
Oct 02 11:22:27 user-83BV gnome-shell[2293]: Meta.Rectangle is deprecated, use Mtk.Rectangle instead
Oct 02 11:22:27 user-83BV gnome-shell[2293]: Meta.Rectangle is deprecated, use Mtk.Rectangle instead
Oct 02 11:22:27 user-83BV gnome-shell[2293]: Meta.Rectangle is deprecated, use Mtk.Rectangle instead
Oct 02 11:22:27 user-83BV gnome-shell[2293]: Meta.Rectangle is deprecated, use Mtk.Rectangle instead
Oct 02 11:22:27 user-83BV gnome-shell[2293]: Meta.Rectangle is deprecated, use Mtk.Rectangle instead
Oct 02 11:22:33 user-83BV rtkit-daemon[1793]: Supervising 9 threads of 6 processes of 1 users.
Oct 02 11:22:33 user-83BV rtkit-daemon[1793]: Supervising 9 threads of 6 processes of 1 users.
Oct 02 11:23:21 user-83BV gnome-shell[2293]: Meta.Rectangle is deprecated, use Mtk.Rectangle instead
Oct 02 11:23:21 user-83BV gnome-shell[2293]: Meta.Rectangle is deprecated, use Mtk.Rectangle instead
Oct 02 11:23:21 user-83BV gnome-shell[2293]: Meta.Rectangle is deprecated, use Mtk.Rectangle instead
Oct 02 11:23:21 user-83BV gnome-shell[2293]: Meta.Rectangle is deprecated, use Mtk.Rectangle instead
Oct 02 11:23:21 user-83BV gnome-shell[2293]: Meta.Rectangle is deprecated, use Mtk.Rectangle instead
Oct 02 11:23:21 user-83BV gnome-shell[2293]: Meta.Rectangle is deprecated, use Mtk.Rectangle instead
Oct 02 11:23:21 user-83BV gnome-shell[2293]: Meta.Rectangle is deprecated, use Mtk.Rectangle instead
Oct 02 11:23:21 user-83BV gnome-shell[2293]: Meta.Rectangle is deprecated, use Mtk.Rectangle instead
Oct 02 11:23:21 user-83BV gnome-shell[2293]: Meta.Rectangle is deprecated, use Mtk.Rectangle instead
Oct 02 11:23:21 user-83BV gnome-shell[2293]: Meta.Rectangle is deprecated, use Mtk.Rectangle instead
Oct 02 11:23:21 user-83BV gnome-shell[2293]: Meta.Rectangle is deprecated, use Mtk.Rectangle instead
Oct 02 11:23:21 user-83BV gnome-shell[2293]: Meta.Rectangle is deprecated, use Mtk.Rectangle instead
Oct 02 11:23:21 user-83BV gnome-shell[2293]: Meta.Rectangle is deprecated, use Mtk.Rectangle instead
Oct 02 11:23:21 user-83BV gnome-shell[2293]: Meta.Rectangle is deprecated, use Mtk.Rectangle instead
Oct 02 11:23:21 user-83BV gnome-shell[2293]: Meta.Rectangle is deprecated, use Mtk.Rectangle instead
Oct 02 11:23:21 user-83BV gnome-shell[2293]: Meta.Rectangle is deprecated, use Mtk.Rectangle instead
Oct 02 11:23:21 user-83BV gnome-shell[2293]: Meta.Rectangle is deprecated, use Mtk.Rectangle instead
Oct 02 11:23:21 user-83BV gnome-shell[2293]: Meta.Rectangle is deprecated, use Mtk.Rectangle instead
Oct 02 11:23:21 user-83BV gnome-shell[2293]: Meta.Rectangle is deprecated, use Mtk.Rectangle instead
Oct 02 11:23:21 user-83BV gnome-shell[2293]: Meta.Rectangle is deprecated, use Mtk.Rectangle instead
Oct 02 11:23:21 user-83BV gnome-shell[2293]: Meta.Rectangle is deprecated, use Mtk.Rectangle instead
Oct 02 11:23:21 user-83...

[Daniel van Vugt (vanvugt)]

Those log messages are not relevant here. They are being tracked in bug 2034664 and bug 2007742.

[Connor Nolan (thebrokenrail)]

This issue also occurs semi-randomly when making normal touchscreen motions. For instance, sometimes I'll be scrolling through a webpage, the suddenly Firefox will un-maximize itself (turning into a normal window), and the cursor will get locked into the drag state. As per this issue, the system is then rendered inoperative until I kill Firefox (the active window).

This however, is not consistently reproducible, where as dragging from the top bar will cause the issue 100% of the time. It is by no means uncommon though, it is actually quite annoying to have my entire system freeze up semi-regularly and require me to manually restart Firefox (in fact, it happened while writing this comment).

I have also done some more testing.
- Minimizing the active window (using wmctrl) from a virtual console does not solve the issue.
- Starting a new window from a virtual console does not solve the issue.
- Consistently, the only way to resolve this issue is the kill the active program.

[Connor Nolan (thebrokenrail)]

The bug is even worse if you just tap on the top bar, rather than drag. If you just tap, the window will un-maximize and also get trapped in the "snap to half of screen / tiling hint" thingy (see attached screenshot).

It gets worse though. While normally killing the foreground program works around the bug and makes the system usable again, if you kill the program while also trapped in the tiling thingy, it will also crash GNOME entirely.

Here's the stack-trace:

Oct 09 15:30:50 user-83BV gnome-shell[335512]: Error in size change accounting.
Oct 09 15:30:50 user-83BV gnome-shell[335512]: **
Oct 09 15:30:50 user-83BV gnome-shell[335512]: libmutter:ERROR:../src/core/window.c:5469:meta_window_get_workspaces: code should not be reached
Oct 09 15:30:50 user-83BV gnome-shell[335512]: Bail out! libmutter:ERROR:../src/core/window.c:5469:meta_window_get_workspaces: code should not be reached
Oct 09 15:30:50 user-83BV gnome-shell[335512]: GNOME Shell crashed with signal 6
Oct 09 15:30:50 user-83BV gnome-shell[335512]: == Stack trace for context 0x5570e87f79d0 ==
Oct 09 15:30:50 user-83BV gnome-shell[335512]: #0 5570e88bee48 i file:///<email address hidden>/src/extension/tilingWindowManager.js:99 (2597789ad9c0 @ 78)
Oct 09 15:30:50 user-83BV gnome-shell[335512]: #1 5570e88bed70 i file:///<email address hidden>/src/extension/tilingWindowManager.js:1291 (2597789b45b0 @ 95)
Oct 09 15:30:50 user-83BV gnome-shell[335512]: #2 5570e88bece8 i file:///<email address hidden>/src/extension/tilingWindowManager.js:431 (2597789addd0 @ 17)
Oct 09 15:30:50 user-83BV gnome-shell[335512]: #3 5570e88bec58 i resource:///org/gnome/shell/ui/init.js:21 (1a1d6a070ba0 @ 48)

Here's the crash report: https://errors.ubuntu.com/oops/8eae4f20-66d9-11ee-9abb-fa163ec44ecd

[Daniel van Vugt (vanvugt)]

Interesting. That assertion was meant to be fixed 3.5 years ago in bug 1845281. But it's definitely a different bug since that one is fatal and this one is not.

[Connor Nolan (thebrokenrail)]

Also, I checked and this bug does not occur on Wayland.

[Connor Nolan (thebrokenrail)]

This bug also occurs even if all built-in extensions are disabled (desktop icons, Ubuntu Dock, etc).

[Connor Nolan (thebrokenrail)]

If I lock the system while it is frozen (by closing the laptop's lid), the lock screen will be usable, but once I log back in, the system will still be frozen (until I kill the foreground process). However, the cursor will be a normal cursor instead of the "dragging" cursor.

Also, something I discovered: if I use two-fingers at once (multitouch), I can interact with the focused window. However, it is very limited and glitchy. As with before, the only way to return the system to a usable state is to kill the foreground process. All other events (including Alt-F2) except for TTY switching (Ctrl-Alt-F3) are still completely ignored by GNOME, rendering the system frozen.

[Connor Nolan (thebrokenrail)]

Can somebody please try to reproduce this? I would like to know if I am going insane or not.

Because I lose a little bit of my sanity every time I have to kill Firefox and lose all my tabs because GNOME randomly decided to ignore all user input until I kill Firefox. Firefox's session recovery does not work perfectly. Sometimes I'll spend time typing something up, just this bug to occur, and then I have to kill Firefox so I can actually use my system, just for everything I've been typing to just be gone.

I'm sorry if it's annoying to get these semi-regular comments from me about this bug, but it happens to me multiple times a day and I do not know enough about X11 and GNOME's inner-working to fix it myself. So giving extra info to people who might be able to fix it is the only thing I can do right now.

[Launchpad Janitor (janitor)]

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

[Daniel van Vugt (vanvugt)]

Confirmed, but I had to have a window maximized before it occurred for me.

[Daniel van Vugt (vanvugt)]

Importance is set to Medium because it seems pretty rare that someone will be using Xorg and a touchscreen at the same time. Hence there are no other reports of the issue yet.