I'm using FF Quantum, v68 64 bit. This add-on ROCKS. I've had it going for several hours now without any ads. Spectacular.
I want Pandora to be able to make at least some $$ with ads, so what I think I'll do is use the extension when I'm working around the house, and use the traditional way (with ads) when I'm being lazy on the recliner. Everybody wins.