I would never, ever, use a browser that is not forced isolated with SBIE to a ram drive. I mean, that's just dumb. Now, as far as Firefox addons go, the less addons you use the better; because it limits the potential attack surface. There are only two that I must use; uBo and violentmonkey. With those the benefits outweigh the risk. In Firefox/Waterfox you can tweak about:config preferences so that the need for man privacy/security extensions is not needed. The same cannot be said for anything chrome based, at least to the same extent.
