Fix updating context menu
Fix updating context menu

Check if the active controller exists.

carpet-berlin/web-scrobbler,fakelbst/Chrome-Last.fm-Scrobbler,galeksandrp/web-scrobbler,galeksandrp/web-scrobbler,david-sabata/web-scrobbler,david-sabata/web-scrobbler,carpet-berlin/web-scrobbler,inverse/web-scrobbler,inverse/web-scrobbler,fakelbst/Chrome-Last.fm-Scrobbler