docs: private void clearArt(DeviceAnnouncement announcement) {
          final int player = announcement.getNumber();
          // Iterate over a copy to avoid concurrent modification issues
          for (DeckReference deck : new HashSet<DeckReference>(hotCache.keySet())) {
              if (deck.player == player) {
                  hotCache.remove(deck);
                  if (deck.hotCue == 0) {
                      deliverAlbumArtUpdate(player, null);  // Inform listeners that the artwork is gone.
                  }
              }
          }
          // Again iterate over a copy to avoid concurrent modification issues
          for (DataReference art : new HashSet<DataReference>(artCache.keySet())) {
              if (art.player == player) {
                  artCache.remove(art);
              }
          }
      }