Just added this extension today to Firefox on Mac running on High Sierra, turned on a Youtube playlist I created which was filled with ads at the start of every video, and not one ad appears now, it's almost too good to be true

Work very well to remove youtube ads

Works really well. YouTube was full of ads and unwatchable before this extension. Now I can watch ads free with this extension. I can't support directly by financial means, but I am sharing this extension to others.