Gnome Shell clock is truncated/corrupt on the right side

[Michał Obeats]

When clock changes value, it doesn't displaying time properly

[Daniel van Vugt (vanvugt)]

Yes indeed. I'm also seeing this bug in the gnome-shell top panel.

[Launchpad Janitor (janitor)]

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

[Sebastien Bacher (seb128)]

Thank you for taking the time to report this bug and helping to make Ubuntu better. Please execute the following command, as it will automatically gather debugging information, in a terminal:

  apport-collect 1882291

When reporting bugs in the future please use apport by using 'ubuntu-bug' and the name of the package affected. You can learn more about this functionality at https://wiki.ubuntu.com/ReportingBugs.

[Daniel van Vugt (vanvugt)]

I don't think that's necessary in this case. This bug has been happening for a year or so at least already.

[Sebastien Bacher (seb128)]

@Daniel, it would tell us if the users having the problem use xorg or wayland and also having at least a journal log from someone who had the issue would tell us if there is any warning printed at the time. Or do you have an idea what the issue is? (in which case maybe dump some details in the report?)

how often does it happen? how do you trigger it?

[Daniel van Vugt (vanvugt)]

It's a small rendering glitch which doesn't happen reliably or on demand.

The problem occurs when the width of the digital clock shrinks depending on the font width like:

  12:30 -> 12:31

But I have struggled to reproduce it when I want to.

[Daniel van Vugt (vanvugt)]

Just happened to me again on focal. Annoyingly, the act of taking a screenshot corrects the glitch before the screenshot is taken. Seems screenshotting forces a full screen redraw.

[Harm van Bakel (hvbakel)]

As a potential workaround I've noticed that changing to a fixed-width clock font seems to avoid the corruption issue. The font family can be changed using a custom gnome-shell.css, containing e.g.:

#panel .clock-display { font-family: Ubuntu Mono; font-size: 15px; }

[Travisgevans (travisgevans)]

I've been seeing it too in 20.04 (Focal), using NVIDIA binary drives and Xorg. I usually see it on the top bar (has happened several times over the past couple of days) but I've also seen it at least once on the lock screen. It seems that moving the mouse pointer over the time corrects it temporarily until the glitch next happens.

I could run an apport-collect command on this bug if anybody is still interested.

[Leon White (strophy)]

ProblemType: Bug
ApportVersion: 2.20.11-0ubuntu50.5
Architecture: amd64
CasperMD5CheckResult: skip
CurrentDesktop: ubuntu:GNOME
DisplayManager: gdm3
DistroRelease: Ubuntu 20.10
InstallationDate: Installed on 2021-01-16 (102 days ago)
InstallationMedia: Ubuntu 20.10 "Groovy Gorilla" - Release amd64 (20201022)
NonfreeKernelModules: nvidia_modeset nvidia
Package: gnome-shell 3.38.2-1ubuntu1~20.10.1
PackageArchitecture: amd64
ProcEnviron:
 TERM=xterm-256color
 PATH=(custom, no user)
 XDG_RUNTIME_DIR=<set>
 LANG=en_US.UTF-8
 SHELL=/bin/bash
ProcVersionSignature: Ubuntu 5.8.0-50.56-generic 5.8.18
RelatedPackageVersions: mutter-common 3.38.2-1ubuntu1~20.10.1
Tags: groovy
Uname: Linux 5.8.0-50-generic x86_64
UpgradeStatus: No upgrade log present (probably fresh install)
UserGroups: adm cdrom dip docker lpadmin lxd nordvpn plugdev sambashare sudo
_MarkForUpload: True

[Leon White (strophy)]

apport information

[Leon White (strophy)]

apport information

[Leon White (strophy)]

apport information

[Leon White (strophy)]

apport information

[Leon White (strophy)]

apport information

[Leon White (strophy)]

I'm experiencing this in Ubuntu Groovy 20.10 as well, but I generally only notice it in the gnome top panel. Moving the mouse over the clock or attempting to take a screenshot clears the display error. I've attached photos of my screen and submitted details from `apport-collect`, let me know if I can provide anything else.

[Travisgevans (travisgevans)]

Discovered this upstream bug report:
https://gitlab.gnome.org/GNOME/gdm/-/issues/714

Allegedly the problem affects fonts that don't provide the oddball ratio character GNOME insists on using for the clock colon, including the default Ubuntu font. This can also cause the colon to render incorrectly depending on which fonts are installed on the system and what the GNOME interface font is set to.

I'm going to try the Cantarell font (the upstream GNOME default font, I think) and see if it resolves the issue.

[Daniel van Vugt (vanvugt)]

I don't think that bug is related to this.

This bug is about rasterization and displaying pixels from a previous frame, which no mistake in the font itself can be responsible for. Also the colon bug is not visible in the screenshots of comment #1 or https://gitlab.gnome.org/GNOME/gnome-shell/-/issues/2912

They are separate bugs unfortunately.

[Leon White (strophy)]

Just posting to update that this still occurs for me in Ubuntu Impish 21.10 (which ships with Mutter 40.5), looks like the fix will arrive in the next major version of Mutter?

[Daniel van Vugt (vanvugt)]

Yes the fix is scheduled to arrive first in Ubuntu 22.04. Although I have not seen the bug in a long time myself so I won't rush backporting the fix until we're sure it's working in 22.04.

[Jaromir Obr (jaromir-obr)]

I can confirm that moving of mouse cursor over the time in time widget fixes the issue (temporarily, because it usually occurs in a few minutes again).
Also if I press "PrtScr" to save screenshot, the issue is fixed itself.

Tested with Ubuntu 21.10, Gnome 40.4.0, Wayland.

[Ali Devrim OĞUZ (devrim-oguz)]

I experience the same issue on 20.04.3 LTS, I think the issue is just lazy pixel updating. When the clock changes numbers, a column (maybe a couple columns) of pixels get stuck in the side of the clock, resulting in a smudge on the side of it. Issue gets resolved by moving the mouse there because it updates the pixels in that area.

[Daniel van Vugt (vanvugt)]

We don't need to guess because there's already a fix coming in the next GNOME version:

https://gitlab.gnome.org/GNOME/mutter/-/commit/867db93043

[Launchpad Janitor (janitor)]

This bug was fixed in the package mutter - 41.3-1ubuntu1

---------------
mutter (41.3-1ubuntu1) jammy; urgency=medium

  * Merge with debian, includes these upstream changes:
    - window: Don't change workspaces of unmanaged windows (LP: #1933996)
    - backend: Reset idletime when unplugging the power cable (LP: #1945121)
    - clutter/text: Invalidate actor paint volume when it has changed
      (LP: #1882291)
    - backends/native: Ensure pointer is onscreen in input thread (LP: #1933186)
    - OSK Enter, space and backspace keys don't work when typing in Greek
      (LP: #1820523)
    - window: Don't change workspaces of unmanaged windows (LP: #1932328)
  * Remainig changes with debian:
    - debian/gbp.conf: update upstream branch to point to ubuntu/master
    - debian/patches/x11-Add-support-for-fractional-scaling-using-Randr.patch:
      + X11: Add support for fractional scaling using Randr

mutter (41.3-1) unstable; urgency=medium

  * New upstream release:
    - Check keyboard serials for activation
    - Fix mixed up refresh rates in multi-monitor setups (LP: #1788535)
    - Allow disabling HW cursors
    - Improve damage handling (LP: #1872870)
    - Consider xrandr flags for advertised modes
    - Ensure constraints after client resize
    - window-group: Disable culling when rendinging clone to offscreen buffer
    - Fix workspace switch animation in default plugin
    - Fix unfullscreening of window that were mapped fullscreen
    - Fix DMA-BUF screencasts with unredirected fullscreen windows
    - Fix orientation changes on devices with 90°

mutter (41.2-2) unstable; urgency=medium

  * Team upload
  * d/p/Consistently-pass-timestamp-as-uint64-when-creating-MetaS.patch:
    Add proposed patch to fix FTBFS on 32-bit architectures
  * d/patches: Update to 41.2-6-g7b64c159a
    - Surface damage viewport improvements
  * Update patch metadata with upstream status

mutter (41.2-1) unstable; urgency=medium

  * Team upload

  [ Simon McVittie ]
  * New upstream release
  * d/patches: Drop patches that were applied upstream
  * d/patches: Update to upstream gnome-41 branch commit 41.2-3-g5d0c26631
    - wayland: Check keyboard serials for activation
    - Sync refresh rate to the correct monitor for maximized/full-screen
      apps in a multi-monitor layout
    - Add a debug environment variable to disable hardware cursors for
      faulty hardware and drivers

  [ Laurent Bigonville ]
  * debian/rules: Disable systemd support on non-linux architectures

mutter (41.1-1) unstable; urgency=medium

  * Team upload
  * New upstream release
  * Drop a patch that came from upstream
  * Update Lintian overrides
  * Replace patches for #995929 with the version that was applied upstream
  * Remove workaround for #994806
  * d/libmutter-9-0.symbols: Ignore removal of clutter_stage_capture_into.
    Nothing else in Debian references this symbol, except for forks of
    the mutter codebase.

mutter (41.0-5) unstable; urgency=medium

  * Team upload
  * Merge packaging from unstable
    - No changes relative to 41.0-4, except for the changelog
  * Close #995929 via changelog.
    The patches in 41.0-4 seem to have been successful.
  * Release to...