1. When updating now-playing, prefer trackartist and trackartist_ids to artist and artist_ids if these are set.
2. Use first of trackartist_ids for artist_id, if this is set.
3. Fix removing a selection of favourites, when Material is set to order the favourites. Need to delete from the highest favourite ID to the lowest, but sorting can corrupt this order.
4. Don't display loaded playlist name in queue.
5. Use "playlistcontrol cmd:load" (etc) to load playlists.
6. Colour repeat, shuffle, and power icons when active.
7. Show cover-art in playlist listings.
8. Fix play/pause button in standalone now-playing view.
9. When updating player list, check if current player's name has changed.
10. Take copy of player ID when updating settings, to prevent the real player object being modified.
11. Close menus and dialogs with 'esc' key.
12. Correctly update power state of other players.