Yeah, I've had the same problem even since the beta versions and never pinned down why. While I don't know the exact cause of it, I know that it only happens when I have hardware acceleration turned on in my BYOND preferences. If not, it appears normal.
But I also run on a toaster, so take that as you will.
I've did what Krath do, yeah, it "fixes" the profile's bug in the trade of wrecking the game's overall quality. Seems to be some sort of graphics hardware issue, so maybe it's something personal?
"Show me what you've got, Snake!" ~ Dev, 08/16/2016.