uBlock is not the only add-on that has stopped working. As of right now my extra Firefox themes, Https Everywhere, Privacy Badger and uBlock Origin have all stopped working. Hope Mozilla gets this straightened out soon...

uBlock Origin is a great add-on that does what it's supposed to do. Of all the add blockers I have used in the past this one is the best.

https://support.mozilla.org/en-US/kb/add-on-signing-in-firefox

It's a good solid add-on

Love the addon, but Firefox claims it is corrupt and refuses to install. What gives?

Since today signature required. I changed to Firefox ESR to use it.