This add on does its job but it has one major flaw, in that it will regularly forget its settings, especially if you install FireFox on a new computer and it links back to your older set ups.
It often forgets that I have allowed sites access and blocks things randomly.. It is very frustrating at times. I like it, I will keep using it (for now) but if it keeps forgetting settings and I have to remind it to unblock sites regularly going forward, I am going to drop this.