They hate their users so much they're perfectly willing to compromise their security. "This extension is not actively monitored by Mozilla". But you can't do the responsible thing and build it from source yourself.
Even installing the "Developer Edition" didn't enable to me to install self-built extensions (yes, with that secret flag). And it doesn't even tell you that it doesn't accept unsigned extensions, they claim that the extension is "broken".
The fuck?! This is Apple-level user hostility. Meanwhile Mozilla execs are getting Apple exec-style compensation while driving it further into the ground.