I recently found out that this playlist is not visible to other users when they browse my profile. The playlist is collaborative, but I don't have the option to make it secret or public (I do for other, newer, playlists).
For now, it's not possible to publish collaborative playlists on your Spotify profile. People could vandalize your playlist and that wouldn't be nice. To publish your playlist, turn off collaborative and you should see the option to make your playlist public.
Let me know if you have any other questions!
HuboRock Star 16
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