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.
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.