To be completel frank, I'm dumbfounded that this feature doesn't exist.
When I load up new music, I usually evaluate all the tracks one by one. However, I usually know during the song, or immediately after listening, whether or not I will keep that track in my collection. I think it would be a great feature to be able to just swipe to delete tracks on the fly from a playlist when looking at the actual at the track list. This would be be in addition to having the ability to go through the edit, and then mass delete songs.
This feature is currently available when deleting individual playlists, so I know the functionality exists in general, but I'm unsure of why this wasn't expanded to within the actual playlists themselves. This would turn deleting individual songs from a 4 step process (triple dots, edit, delete, delete) to just 2 steps swipe, delete. I think this not only saves time, but ultimately adds convenience to quickly delete a song vs. going through a menu process to delete an individual song.
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