This makes a nice way to set all your defaults such as privacy protection, do not track headers, and other items you might have to click through the Preferences menu. You can also use the user.js file for any settings in your Firefox config. Now each time Firefox loads it will set those preferences. User_pref('print.print_headerright', '') User_pref('print.print_footerright', '') So in my user.js file I added: // Printer Settings Default off I recently learned from a friend how to disable printing headers/footer on Firefox, thank you! I completely agree the default should be to not include them. It is best not to make changes there but to manually enter them in the user.js file. 💡 Settings made in about:config are saved only to prefs.js. It would not work across different platforms or users. The prefs.js file looks like it could be portable, but it contains too many settings, including paths and system specific items. The prefs.js file already exists in your Firefox profile directory, find the location using about:support in the top bar. This a convenient way to save your browser customizations and apply them on different machines.
The Firefox user.js file stores user settings, the file is loaded each time Firefox starts.
