Each time the browser starts up, if it detects a new add-on that’s been installed by a program, it will disable the add-on and present the user with a dialog box asking them if they would like to keep the add-on disabled or give Firefox permission enable it. This way, Mozilla ensures that unauthorized, privacy-invading add-ons are going to be an issue of the past. The add-on blocking feature will debut next week with Firefox Aurora beta, so it’ll be awhile more before it makes it to the stable build.