for the next update:
- in the playlist header, when auto-pick colours is disabled, then fg2 is now used (from the "MusicExplorerHeader" element)
- in the playlist header, bg2 from the MusicExplorerHeader element is now used
- in the playlist header, although fg2 is used, the "Edit Playlist" text is still slightly lightened
- in the music explorer header ("MusicExplorerHeader", a gradient background colour (bg2) is now supported