Just a small bug (but I'll report it anyway):
If you click the "hamburger button" next to a folder or a song in the library, the icon in the "Add, replace and play" line is missing.
This only happens in Firefox under Windows (tested with Firefox 41.0.2, Win 7 and 8.1).

In Firefox running under Xubuntu, Runeaudio WebApp (Windows and Linux), Internet Explorer and also on my Android Phone the Icon is there.

Im on dev-branch with Raspberry Pi B and B+, both with a HifiBerry DAC/DAC+.
Seems RuneUI is not liking Firefox under my Windows machines

Have a nice day.
Greetings, Michael