I was moving a playlist (A) up to the top of my list for easier access. I accidentally dropped it underneath another playlist (B), and so now it's accidentally a sub-playlist. I tried to move Playlist A out from underneath Playlist B. I cannot. Playlist A is stuck as a sub-playlist underneath Playlist B. It won't budge.
Am I missing something obvious? Or is this a bug? Either way, this is REALLY annoying. Playlist A is now buried inconveniently underneath Playlist B.