I have a user.js, and it has a bunch of user_pref() that are not in the default FF config, so some of them need to be created in the about:config page. Until recently, this has not been a problem ...

Ever since its debut, Firefox has garnered a reputation for being an enormously customizable program, both through its add-on architecture and its internal settings. In fact, many of Firefox’s ...

Now you can safely change them. Should you ever botch something up in about:config and need to restore Firefox, close the browser, and copy that backup of prefs.js to its original location ...

You need to locate and delete the file prefs.js or rename it to something like prefs.js.old. If you see any other “JS” file, rename them as well. Relaunch Firefox. This part usually takes a ...