iPhone 12 mini Screen corner blurred 12 Mini

[Zapdoc]

Just noticed upper left corner of screen extending about 1/3 along top was blurred such that I could not read this part of address line in Safari. Was not there on swiping down to see notifications but was in photos and everything else. Phone owned from first day of release from Apple and screen cover in place from day 1. No damage to screen handled carefully
However after switching off and on again screen became normal !
Any idea
What that was and is it likely to occur again ?

 

[RocketFast]

Never heard of that, sound definitely like a bug. Maybe share a picture of it so we can get a better understanding.

 

[Apple_Robert]

Either an intermittent software bug or “one of” use glitch.