Yes

Doesn't work anymore.

This extension has a lot of features.

It hasn't worked since the beginning of the year and it looks like they gave up on it to fix it. Completely useless add-ons.

doesn't work for Twitch, like advertised

Not anywhere near as extensive as FrankerFaceZ, but it has some useful functions that FFZ lacks, in particular ability to join chat anonymously. I use both BTTV and FFZ for different reasons and they don't conflict with each other, both great extensions on their own.