Show thumbnail of youtube video as artwork
Feature request
Mopidy has a plugin called mopidy-youtube which can be used to stream music from youtube(these songs' track URI starts with youtube). There is no artwork for these tracks, so the thumbnail of the video could be used as artwork.
Also, I noticed that sometimes in full-screen mode, the artwork isn't shown, but it is shown in normal view. Happens for less popular songs and artists mostly. In these cases I think the artwork shown in normal view should be shown in fullscreen as well.