I think it's really just a trim piece and not an actual seal, but I've noticed a few times the rubber strip that runs around the window in the rear hatch has pulled away from the glass (on the upper left) or rolled under itself essentially creating the same effect on the upper left on the side.

I was able to fix it but I have no idea what would cause it. The only thing I could think of is a car wash but the one I use does not use any kind of rotating brush like some of the cheap gas station ones use. Are there any known issues with the rear window like this? I couldn't turn up jack on search for "rear window seal".