Recent, Firefox incident of add-on signature verification failure disables most of the add-ons and failing to install add-on in Firefox as well as in Tor browser . But, IceCat browser wasn't affected by this incident. I was wondering , why IceCat browser was not affected by this incident?
PS: In my IceCat browser I've install some extensions (UBlock origin, NoScript etc) from Mozilla official add-on repository (
https://addons.mozilla.org). And one more question, is it perfectly fine to install add-ons from Mozilla offical repository or should I stick only to add-ons which are maintained by GNUzilla?