This is a tiny thing, but it's been bothering me for a while. When I sort albums from my Inbox and send them to the library through a move command, occasionally the next time I open up Musicbee I'll have the albums in the inbox as "unknown" and 0 tracks. The Album art that it associates them with is the only clue that they were the albums I recently added to the library. Generally, I just delete these phantom albums and that's that, but if there's something in my process I'm doing wrong to prevent it, I'd love to know!
Move command I use in Musicbee
Result (sometimes) after restarting