Right I'm still on 15.5. But random app windows flicker! FLICKER! And it's a brand new 2025 M4 MacBook Air. This is the kind of thing I would expect from like Linux in say 1998?
Was it released for the M4? If so, you might have a hardware problem. Bad display cable, faults on the motherboard, that kind of thing?
Slack flickers a lot for me, no idea why. I haven't updated macOS yet because I don't love the look of the new liquid glass stuff. I think this makes me 2 majors behind now...