Returns the 'root' playlist, which is considered to be a virtual playlist whose children are all the first level playlists.
Returns list of playlists to which the track belongs
as promise
Save list of tracks to playlist file
default filename (if it is absolute path with file extension then dialog for selecting a location isn't shown and file is saved directly)
as promise
Playlists manager class. Access via the global
app.playlists
.Playlists