TL;DR Firefox 15 prevents most memory leaks caused by add-ons, including Firebug.  For many users with add-ons installed this will significantly reduce Firefox’s memory consumption, without requiring upgrades to those add-ons. For those users, Firefox 15 is likely to be faster (sometimes drastically so) and less likely to crash, especially if they have multiple add-ons … Continue reading Firefox 15 plugs the add-on leaks