Whoa, this is the first time I've ever experience image retention on an LCD before. I was listening to music played through my PC, stepped away for about an hour and a half. The PC turned off the DP input after 20 minutes, so then it auto switched over to HDMI input because my Denon receiver outputs an image of Spotify. So that static Denon Spotify image was up for over a little over an hour. I come back, start using the PC and I'm like uhh, what the heck is this faint image on my screen. I go to a solid grey color and I can still see the Denon Spotify image. I started to freak out. Of course you go to worse case and it's burnt it, but it took about 40 minutes to fully fade away.
Crazy..