Mozilla has blocked older versions of the Stop Ads adblock add-on because it sent the entire browsing history of its users to a third party. The browser developer is able to remotely block malicious and problematic add-ons.
The Stop Ads extension should block advertisements, pop-ups and trackers but version 0.0.4 also sent all visited sites to a third party. A 'feature' not required for proper functioning of the add-on and a reason for Mozilla to take measures against this unwanted behavior.
The open-source browser developer used its technology that makes it possible to remotely block add-ons. Firefox users that feel the add-on should be enabled again can do this manually if they want. Stop Ads has 56,000 users and the developers released a new version (0.0.5) to its users that isn't blocked.
