It happens with strictly black borders but I disagree with people saying it’s only noticable at 100% brightness. It’s clearly visible at 40-50% brightness settings for me, and this was the case for all four.
I really really hate myself for getting FOUR replacements, but I think it’s more Apple’s problem, not mine. I think it may be worth posting on this forum since the more widespread it is, the more likely Apple will fix it. Maybe it’s worth it going through all these defects so other customers don’t have to experience it.
Ignore what I said, I apologize - these things aren't cheap and Apple is doing the right thing by letting you get the device that works for you. Apple will use the ones you sent back as refurbs so it is not going to waste. I see a growth of some unreasonable posts and I just assumed. My bad.
Yeah, I think I've seen another thread about this - they have a video where you are supposed to turn up your brightness and everything.
I use my iPad at 20-30% brightness so it's close to what you have.
I prefer dark mode too so my wallpaper is usually black, apps with dark mode on, so any problems with the light would bother me.
Thanks for posting your experience here.