Add a 'Stop after this song' button
What is the problem you are facing?
As a strange guy, I hate stopping a music until it ends so on my music player (which is Quodlibet) I always use the 'Stop after this song' button which stop playing queue when the actual title is finish. Then I'd find cool to have this function on Funkwhale.
What are the possible drawbacks or issues with the requested changes?
I think the only real problem is to find where to put this button as not so much users would use it.
Context
As I said, I know that this function exits in Quodlibet, it is available in Control -> Stop after this song