Well, that would be a lot of work, to create those side by sides.
However, I have this same problem with the tobetter's Ubuntu Wayland images as well.
So this with Panfrost as well as with the Wayland Mali drivers/infrastructure.
Also, I tested Manjaro ARM (KDE Plasma) a while ago, which used neither Panfrost nor the Wayland Mali driver. And the problem was there as well, using llvmpipe for graphics.
I also installed both KDE and Gnome on the N2, on jgmdev's arch linux image, if I remember correct: so same distro, same drivers, different desktop environment, made no difference.
It might be worthwhile to mention again that if you take a screenshot of the desktop using the printscreen button or some such, the screenshot itself is clear.
Which led me to think it of being some kind of monitor or HDMI driver issue. Keep in mind on some monitors, it goes right, on other monitors it doesn't. Same installation.
Update: yeah, just hooked up the N2 with jgmdev's arch linux image (Gnome 40, Panfrost) to my old old monitor, no issues on a Samsung Syncmaster 203B on 1400x1050. So not really comparable, but it really is monitor specific.
Same thing hooked up to my Dell P2319H and LG smallscreen TV/monitor, has these issues. And then, only with the mainline kernel, never saw this with the 4.9 kernel series or with other computers.