I've just noticed that the "on Last.fm" functionality isn't quite working in the latest 7.3 via the Controller.

If you select a song on the Controller and then "On Last.fm" you can navigate to various Last.fm options such as Play Similar Artists Radio but you can't play there from the Controller or add these to the playlist. Doing the same from the web interface works as expected. This was working in 7.2.1.

I also can't see anything in the server.log - which is the best option to enable for debugging?