I expect this is what you saw :Add-ons Blocklist | Mozilla :"AVG SafeSearch, versions older than 8.5, for all applications. Reason: high crash volume and stability issues (see bug 527135)." *https://www.mozilla.com/blocklist/ It is the "AVG Safe Search" extension that is the problem, Mozilla finally disables it, but the if you follow directions to disable the "Link Scanner Component" it makes things a lot easier in Firefox * The extension does not get accidentally enabled * You don't have to worry about use in other profiles * You don't have to worry about a major update to Firefox activating it : * Problematic extensions - MozillaZine Knowledge Base<br>http://kb.mozillazine.org/Problematic_extensions If you're wondering what the extension does, it is similar to what you see on search listings for what McAfee Site Advisor, and WOT extensions do. Mcfee is the only rating system I put value to and it won't be available again until later this month (about 3rd week July 2011) -- hope they really fix it, all the work that was put into databases and virtual servers is wasted if the interface with the browser does not work, crashes or makes search results come back very slow or don't have ratings after the first page.