Add ons must be signed by Mozilla I think. Also, add ons that have privileged access require a special signature that Mozilla only uses for their own add ons. T

Add ons must be signed by Mozilla I think. Also, add ons that have privileged access require a special signature that Mozilla only uses for their own add ons. That's what I meant with signed Javascript. Anyway, this wasn't my main point. It's why you load and execute Javascript from the network in the first place in the content process. It feels to me that banning JS loading would have helped here a great deal and would make exploitation of similar bugs much harder.