Rated 3 out of 5 stars
I took it off after a month. I thought FEBE was really an excellent tool, except for 2 minuses: (1) The one time I really did need a backup, FEBE didn't work to re-establish my Firefox, and so I had to use my ordinary everyday FF backup of my profile instead, which worked perfectly, and is perhaps easier to obtain in the first place. (2) With FEBE backing up Firefox WHILE FIREFOX IS RUNNING, it was also "backing up" maybe a dozen or more data miners and other exploit cookies every time. Then AVG would tell me I had all these things trolling my system, whereas normally Firefox kills those on shutdown and so I can do exactly the same surfing with nothing found later by AVG. So after I'd erased my FEBER backup files a number of times, I took the extension off.
I'd say FEBE is a really good tool that works but doesn't really achieve what I want.