Technical Details on the Recent Firefox Add-on Outage
https://hacks.mozilla.org/2019/05/technical-details-on-the-recent-firefox-add-on-outage/ [hacks.mozilla.org]
2019-05-09 21:13
Recently, Firefox had an incident in which most add-ons stopped working. This was due to an error on our end: we let one of the certificates used to sign add-ons expire which had the effect of disabling the vast majority of add-ons. Now that we’ve fixed the problem for most users and most people’s add-ons are restored, I wanted to walk through the details of what happened, why, and how we repaired it.
source: L