burn-in

I just noticed my monitor has outlines of the Spotify UI burned into the screen, the outlines of it are there regardless of what I put on the display. Photos below: I have Spotify open most of the time on that monitor, but I turn the PC off every night and often move things in and out of that...

I've bought a Lenovo G25-10 3 days ago and it came with this weird kind of line shadow on the lower side of the display. It's mostly visible on darker colors, especially gray, on bright colors you can't really see it. I have no idea how to describe it and I have found no information about this...