RE: iPad 9th Generation: I just noticed this on my 9th gen that I bought a month or so ago (well actually I had noticed it before when I first got it but didn't think it would come up into play). Then I started watching vids tonight on it and was like OMG, what have I done? Now I can't exchange it so I'm stuck with it. I have the same issue you do, bottom right hand corner, the bleeding affect comes out about maybe 1" from the edge of the display. There is a bit more bleeding around edges/corners but it's not as obvious as that lower right hand corner is. Kinda pissed about this but I guess it is what it is now.
EDIT: I just took a pic of the screen using a screen test app to check the backlighting, it actually looks worse in the photo than it does looking at the iPad lol, wow this is crazy! I guess these iPhone cameras ain't messin' around. 😂🤣
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