iPhone 12 mini - smudge/blur when black turns to any colour

I've got a new iPhone 12 mini. One of the first things I checked is whether it's affected by the green tint issue. Luckily it is not. However I've noticed that whenever any colour is supposed to be displayed in a part of a screen that's black (like when scrolling) there is a moment when reddish blur appears (before the actual colour appears). It's only for a brief moment so it's rather impossible to take a photo/screenshot of it.

Apple Support in an article does state that there might be slight blur or change of colour in such scenarios and it's inherent to OLED displays, but because it's written in an ambiguous way I wanted to check if the effect I'm noticing is actually what Support refers to. Thanks in advance for any help or comments.

I should add that I had just updated to iOS 14.5.1 and I'm not sure if that issue didn't appear earlier or I simply didn't notice it earlier.