What prevents malware from injecting itself into Firefox process, hook few functions and empty bank accounts? Browser addons are dangerous, sure. But everything is dangerous. I'd say that malware is more dangerous than browser addons. Yet I'm living in a world where it's ridiculously easy to run an arbitrary exe file. Why Firefox wants to make it different for addons? I could understand those measures for iOS Firefox version. May be Firefox could mimic macOS behaviour (need right click to run unsigned app). But making walled garden in the world where everyone can just jump over that fence does not make any sense for me.