Only thing I would add is that the Playlist does not have to be in the root - it can be in an Artist or Album folder. BUT you have to create the playlist in a different format!
if you want to be very bored, here is the link to the doc I created when this was first asked. But it is long and boring - don't say I didn't warn you
Playlists
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S90 2017 D4 Inscription Osmium Grey, Winter Plus HUD, Xenium, Plus various options