Mozilla blocked malicious Firefox add-ons installed by 455,000 users after discovering they were abusing the proxy API to block Firefox updates. Mozilla has added a system add-on dubbed Proxy Failover to block similar malicious addons to abuse the same API. Mozilla advises users to update their web browsers to at least the latest release version (Firefox 93), which can make sure that they’re protected from adding-ons abusing proxy API. Microsoft Defender is the only anti-malware solution that can detect the add-ions as malicious.”]