Moving/adding songs in the playlist should undo any sorting

Say you sort by Title.

Then you drag any song to another location. (or perhaps, add more songs to the playlist)

Now, the playlist is no longer sorted by Title.

Yet, the "column headers" display that the playlist is still sorted by Title.

My suggestion: when the playlist is changed in any way*, the playlist should return to the "unsorted" state.

*note: Hmm... but perhaps not when removing songs from the playlist?