Coloured dots randomly appearing on my iPhone screen

I have been experiencing this since last month. Tried resetting iOS, tried removing the glass screen protector. It doesn’t seem to be an issue with my screen (hardware) itself, the dots are completely random and keep changing place. It affects mostly photos(screenshots as well, so I don’t think it’s related to the camera) videos and instagram. Any ideas? Please find screenshot below as an example.

[Edited by Moderator]

Original Title: Color dots all around the screen