This is deeply disappointing. Two details: the extensions need to be signed by Mozilla , and only US English speakers will be allowed to disable this requirement. The point of free software is that users, individually and collectively, are free to modify it as they wish, without requiring approval from third parties. (And of course to use, copy, and redistribute.) This is a sharp turn away from the free-software etho…
Mozilla have been doing odd things in recent years, almost like they are transitioning into an authoritarian movement. Want to use unsanctioned extensions? No, go away. Want to use non-secure HTTP? Sure, but we will take away your features. Want to work for them but have unapproved views? Fired. All this is from viewing them as an outsider, so you never know, but something is different.
And caring about users' security is to be commended.