I encountered a weird "bug" I guess around the Stone of Barenziah in Wuunferth the Unliving's quarters. In the Trivia section of the "Stones of Barenziah" page it mentioned that the Stones can be collected from private areas without reprisal (they aren't stealable items).
Either that is untrue or I've just encountered a new bug because I picked it up and was immediately arrested by the Imperial Guard standing nearby and I heard Wuunferth yell at me. Bounty of 250 gold. I don't ever remember anything like this happening in all my years of playing the game.
I can't go back and redo because I've moved too far ahead now but have I missed something? By rights that shouldn't have happened. Playing on Nintendo Switch.