Excellent addon, one of my top 2 addons I use constantly. I can't give 5 stars because of an issue, where if a page has more than 1 embedded video, the addon does not migrate the custom volume to the next video.
Say I set video 1 at 440%, when I open video 2, volume is still set at 440% in addon, but at the volume of 100% through speakers. I have to reset addon to 100%, then back up to 440% for each video.