Cortland

A sleek, modern, macOS-inspired theme for Firefox.

Description

This is is a collection of CSS code that changes the look and feel of Firefox.

Cortland turns the default UI of Firefox into an intuitive, modern interface, and supports both both light and dark themes, too!

This theme currently supports MacOS and Linux. Windows is not supported (yet). Firefox 70+ is recommended.

Installation

1. Download this project.
2. Go to about:support in Firefox.
3. Under Application Basics > Profile Directory, click the Open Directory button.
4. Copy the chrome folder from this project into the profile directory folder.
5. Go to about:config.
   • Click Accept the Risk and Continue.
   • Search for toolkit.legacyUserProfileCustomizations.stylesheets and set it to true.
6. Open the Firefox menu (☰), click More tools, and then click Customize toolbar.... If you are using an older version of Firefox, simply open the menu (☰) and click Customize....
   • Ensure that the Title Bar checkbox is unchecked.
   • Drag the new tab button out of the tabbar and into the headerbar.
7. Go to about:addons.
   • Click on the Themes button in the sidebar.
   • Look for System theme - auto and click Enable if it is disabled.
8. Restart Firefox.
9. Enjoy your new Firefox theme!

Issues and features

Bugs

Think something is wrong? Create an issue and I'll see what I can do.

Feature request

It's always nice to see new features. If you think something would make Cortland even better, create an issue and suggest your idea!

Uninstallation

Still not content with this theme? Simply re-open your Firefox profile directory and delete the chrome folder. Then restart Firefox. This will return Firefox to the default theme.

Credits

Based on the Qogir Firefox theme.