Is anyone else having this issue? I saw that someone had a similar issue where marks don't appear until switching brushes. I'm guessing this stems from a similar bug. Every time I draw, the marks don't appear until I've switched layers. It doesn't matter which layer I start with, or which layer I switch to.

Yes, someone else has got this issue. It gets reported one or two times a day, and is the top entry in the FAQ: https://docs.krita.org/KritaFAQ#Krita_s ... Intel_GPUl .

But... It's not a bug in Krita. It's a bug in the Intel display drivers. And none of the developers have the right hardware/driver combination to reproduce the issue, because we're keeping our systems up to date.