I was wrong on WebExtensions

WebExtensions > legacy addons.
Firefox legacy addons basically have unrestricted, full access to everything browser does.
They are barely step behind ActiveX. They can download arbitrary data and execute it.

>>13
Completely wrong context. The user still has to install the addon in the first place.

>>14
Actually I do. I use a physically separate machine for trying out suspicious executables that I can't be bothered decompiling and analysing, but there hasn't been too many of those over the years...

...and I've been doing that for decades without any problems. Whereas some dumbfucks will still manage to screw themselves multiple times with a highly-locked down and otherwise useless-for-doing-anything-productive mobile device.