Mozilla explains why all Firefox add-ons broke at once
 

Firefox Chief Technology Officer Eric Rescorla has written a detailed blog post explaining exactly how the browser's add-ons came to break all at once last week, how it was fixed, and how the company will avoid another 'armagadd-on' in the future.

https://www.engadget.com/2019/05/10/...broke-at-once/