Don't know if this counts as a bug so I decided to ask about this first...
I got a couple of auto-playlists put into folders. When I click on some of those folders MB lists all the tracks included in those playlists as one full result (which I see as intended behaviour) while other folders don't even though the auto-playlists share the same logic.
In the example above clicking on the "2013" folder shows all the tunes from the sub-lists while "2014" does not. The individual auto-playlists work fine, though.