Visual artifact 1px vertical white line right side of the wallpaper

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Thanks. Please try removing your extensions in case they are the cause:

  cd ~/.local/share/gnome-shell/
  rm -rf extensions

and then log in again.

Done. There is no change. The artifact is still present.

In the past I had seen a 1px gap down the right side of the wallpaper on Intel, but I think that was only during desktop zoom and I can't reproduce it today. Whatever the cause was might still be present and might only be manifesting with AMD graphics. Just a theory.

That could very well be the case. It does not appear when the desktop is initially loaded, but shortly after a refresh(?). If I keep the second monitor (TV) active, the scaling workaround does not work - the lines on both monitors come back when set back to 100% scale. If I click the desktop the line disappears from the monitor that was clicked - and comes back once the desktop is no longer focused. An annoying little thing that I'm sure is equally annoying to figure out.

Can you attach a photo or video of the issue?

Picture one, default when the desktop is no focused.

Picture two, after the desktop was scaled to 125% and then back to 100%, and the Settings window is not closed, yet (the white line disappears after the Settings window is closed).

Single monitor examples. The same happens when I activate the second monitor, with the exception that the white lines are both on the second display before closing the Settings (if I recall correctly). Would you like pictures of the two monitor setup, as well? Or do these two pictures demonstrate the artifact well enough so that they are not needed?

Thanks, that's enough info.

My immediate thought is that it might relate to mutter's background rendering code which aggressively tries to limit the number of wallpaper pixels it redraws each frame. Maybe there's an off-by-one mistake in that code.

I would not know. Nevertheless, I consider this bug report as a heads up in case you encounter it or something similar in the future. It is nothing critical, and the workaround does work, even though applying it every time I log in to Ubuntu will probably get tedious in the long run. Does this even affect others? No idea.

I've not seen any other reports of this bug.

If it is mostly only visible on AMD graphics and less than 6% of Ubuntu users are using AMD graphics, intersected with the small proportion of users who are willing to report bugs instead of ignoring them, it's a small intersection so unsurprising it took this long to be reported.

I need to switch to AMD to work on another bug soon so I will check on this one too.

An update since I have a new computer with a fresh, clean install of Ubuntu 22.04.3 LTS...this may very likely be a theme issue. It is not present when using the default theme. It appears when trying to change the Applications theme to - for example - Ambiance (the one I would prefer).

Consider this solved?

If the bug still occurs with any theme then we should keep it open.