Firefox, may I tell you what the free Web really needs? A docker-like environment for websites. The environment can arbitrarily override anything, from JS built

Firefox, may I tell you what the free Web really needs? A docker-like environment for websites. The environment can arbitrarily override anything, from JS built-ins to CSS rules, and do that in such a way that the underlying website would never know about the shim layer. A useful bonus would be limiting CPU time spent by the website. The former can be marketed as a privacy feature and the latter as comvating global warming.