TLDR: People complained so we&#x27;re back-pedaling.<p>There are good technical reasons for requiring signed add-ons. Well, maybe not so much &quot;good&quot; but necessary because of other bad things in Firefox that prevent a less extreme requirement from being implemented.<p>But the signing requirement isn&#x27;t what upsets anyone. It&#x27;s that add-ons must be signed _only by Mozilla_. The whole mess could have been avoided from the start by saying that add-ons must be signed by a trusted certificate but the end-user gets to choose what certificates are trusted.