Firefox 42 will not allow unsigned extensions

Mozilla is doing everything to stop using their browser.

And instead people are going to use what?

not sure yet, but as soon as there's something I'm making the switch.

Too many extensions are required to try to make firefox into something usable, mainly reverting changes or fiwing broken or missing features: ad blocking, sidebar, download manager, bringing back the add on bar, putting back the ability to disable javascript, session manager, cookie manager ability to take screenshot, mouse gestures, tab manager, …