Mozilla over the weekend scrambled to come up with a fix for a bug that crippled most Firefox add-ons.
Engineers issued an update for the desktop browser Sunday afternoon that addressed the issue. That update followed a Saturday hotfix released via a little-known component that lets Mozilla feed pre-release code to Firefox users and then collect data from the browser.
The problem was traced to the certificate used by Mozilla to digitally sign Firefox extensions. When the organization neglected to renew the certificate, Firefox assumed the add-ons could not be trusted – that they were, in other words, illegitimate at best, potentially malicious at worst – and then disabled any already installed. Add-ons could not be added to the browser for the same reason.
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