In addition to the built-in Customize feature (see Customize Firefox controls, buttons and toolbars at Mozilla Support), you can modify the appearance of Firefox using the powerful userChrome.css feature.
userChrome.css holds style rules for modifying Firefox's user interface. You can find users on the web offering a wide range of ready-to-paste style recipes, and communities where you can request help with rules to make your Firefox look just the way you want. And it's all free.
Ready to learn more?
- What is userChrome.css and what can it do?
- How to Create a userChrome.css File
- Resources for Style Recipes and Tools
- What is Autoconfig Startup Scripting (AKA userChrome.js)?
"Hot News" links:
- Firefox 89 – Styling the New Proton UI
- (Firefox 75) Megabar – Configuring and Styling the Firefox Address Bar
- Firefox 69 Broke It!
This site is not maintained by or affiliated with Mozilla, the maker of Firefox. For more information on Firefox, please visit: https://www.mozilla.org/firefox/.