It would be nice if we could use our custom order while adding new songs to playlists. This order only works in library. When you try to expand your playlists by adding new songs, they're sorted by most recent. It makes it really hard to find the playlist you're looking for, especially when you have a lot of them and have to scroll through to find the one you're looking for.
I think this issue appears only with custom order.
Updated on 2019-09-05
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A similar idea has already been suggested here, so we're going to mark this one as a duplicate.
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Thanks! Stay awesome 🙂