The playlist endpoint contains different tracks than the desktop / mobile client

[jbwl]

Issue found on April 29th 2020

Endpoint(s):

GET https://api.spotify.com/v1/playlists/{playlist_id}/tracks

Scope(s):

• None (application is not using authentication)

Steps to reproduce:

1. Open the API Console
2. GET https://api.spotify.com/v1/playlists/37i9dQZF1DWWQRwui0ExPn/tracks
   (and repeat for more tracks with a changed offset)
3. Compare the list of received tracks with the list of tracks displayed for this playlist in the desktop / mobile client.

Expected behaviour:

The list of tracks received from the API is identical with the list of tracks displayed in the desktop / mobile clients.

Actual behaviour:

The list of tracks received from the API differs from the list of tracks displayed in the desktop / mobile clients. Several tracks that are listed in the API are not in the playlist shown in the clients.

[ritiek]

I think there is a similar issue for this playlist:
https://open.spotify.com/playlist/37i9dQZF1DWTDkgFD3ivE6

If I make a call to the get-playlist endpoint for this playlist, the API response returns some additional "tracks". For example, the 5th track in the API response (which is not present in the playlist when viewing in Spotify Web) on indexing ["tracks"]["items"] is:

{'added_at': '2020-05-14T19:38:02Z',
 'added_by': {'external_urls': {'spotify': 'https://open.spotify.com/user/'},
              'href': 'https://api.spotify.com/v1/users/',
              'id': '',
              'type': 'user',
              'uri': 'spotify:user:'},
 'is_local': False,
 'primary_color': None,
 'track': None,
 'video_thumbnail': {'url': None}}

As one can see, this "track" doesn't really contain any useful information. I'm not sure what it's doing here.