Wacky Workbench Skin Issue?

Every so often, there's a few posters that post with this strange background highlighting. While it isn't exactly noticeable on the skins with a white background/automatic text colour set to black, it becomes a problem on the Wacky Workbench skin, where the text is white by default. It's probably worth mentioning that this isn't the first time it's happened, as I didn't feel it was worth reporting, but since I've been seeing this poster in particular (intentional or accidental) with all of their posts having this weird highlighting, it'd become problematic if other newer members ended up doing the same.