FOSS Post - https://fosspost.org/tutorials/how-to-customize-firefox-57-user-interface
The new Firefox Quantum browser from Mozilla brought tons of new features and updates. It is now faster, lighter and more organized than ever it was before. However, with the new Firefox Quantum technologies which detached the older APIs used for complete themes and other add-ons, users were having a hard time customizing the browser’s interface.
Fortunately, you can easily customize Firefox +57 interface by modifying the default “skin”. You can simply create a bunch of CSS rules which change the Firefox interface however you like. We’ll learn together how to do it in this tutorial.
Step 1: Locate your