OK I really couldn't work out where this should be posted, it's honestly the weirdest bug I have ever experienced. In my Steam Library all of my games under the Sega umbrella like Total War, Alien Isolation, AvP, Dawn of War, Endless Space, Crazy Taxi, etc. have all gotten a random new image in the Steam Library. There's an overlay on every Sega game with Sega Mega Drive, Sega Genesis, Dreamcast, Sega Saturn, Sega Game Gear logos. I don't know if it's to do with another Sega game I have in my library or something.
Screenshot below. Link to my Steam Library: https://steamcommunity.com/id/waaaghzag/games/?tab=all
"I'm gonna stomp 'em to dust. I'm gonna grind their bones. I'm gonna pile 'em up inna big fire and roast 'em. I'm gonna bash 'eads, break faces and jump up and down on da bits dat are left. An' den I'm gonna get really mean." - Grimgor Ironhide