Hey guys, this has nothing to do with Enpass. Mozilla missed updating important certificates, which causes the issues you experience. To solve the problem you have two options:
Wait for Mozilla to resolve the problem with e.g. a rollout of a new Firefox version
Apply the studies mentioned in this post i.e. apply Firefox Preferences -> Privacy & Security -> Allow Firefox to install and run studies. You can disable studies again once you restarted your browser.
After (2) Enpass addon should work again.
Duplicate of