Accessibility: Keyboard Brightness control not operable using keyboard or mouse scrollwheel
At the power settings there is a slider for setting the "Keyboard Brightness". My ThinkPad T460s supports three levels: off, dim, bright
With clicking and/or dragging I could move the slider to either the left-most, center, or right-most position.
However when place the mouse cursor on top of it and use the scroll wheel, I could not move the slider. Same happens when I try to use the cursor keys on the keyboard.
My assumption: When using the scroll wheel or the keyboard, the slider is moved by only a small fraction. So if the left-most position is 0% and the right-most is 100%, it will try to increment it by 10%. It does so, but as the only valid values are 0%, 50%, and 100%, it tries to round it to the nearest value, which is 0%, so it jumps back to where it was. You can see the slider briefly jump a short distance but only very briefly, not much more than a flicker.
While I could just click/drag with the mouse to change the slider, for some people it might be an accessibility issue and thus I believe this should be fixed somehow.
I also figured out that I can move the slider between the left-most and right-most position using the home and end keys on my keyboard, I haven't been able to put it to the middle just using the keyboard. I also consider this not very intuitive.
There is a Fn-key combination on the built in keyboard though which controls this brightness level, so it might not be that much of an issue.
But there might be other areas where there are similar issues with scrollbars. So it might be a general issue with GTK+ scrollbars or a scrollbar might not be suitable for this setting.
Directly above is the control for controlling the built in screen's brightness, but as this has much more granularity, I don't experience this issue there.
This is an upstream bug for https://bugs.launchpad.net/ubuntu/+source/gnome-control-center/+bug/1948486
ProblemType: Bug DistroRelease: Ubuntu 21.10 Package: gnome-control-center 1:40.0-1ubuntu5 ProcVersionSignature: Ubuntu 5.13.0-20.20-generic 5.13.14 Uname: Linux 5.13.0-20-generic x86_64 ApportVersion: 2.20.11-0ubuntu70 Architecture: amd64 CasperMD5CheckResult: unknown CurrentDesktop: ubuntu:GNOME Date: Fri Oct 22 19:16:07 2021 InstallationDate: Installed on 2019-11-25 (697 days ago) InstallationMedia: Ubuntu 19.10 "Eoan Ermine" - Release amd64 (20191017) SourcePackage: gnome-control-center UpgradeStatus: Upgraded to impish on 2021-10-22 (0 days ago)