Real Tabs Userchrome for Firefox

This is a pair of CSS files to correct several modish shortcomings of Firefox's Proton (v89-current) interface that did not previously exist in the Australis (v29-56) and Photon (v57-88) interfaces. It features:

• Contrast between functional areas – viz. active and inactive tabs, and the preferences sidebar – a nice feature of the Photon era that's been squeezed out by Light/Dark modes
• Crisp 1px borders and inset shadow for contrast on text boxes
• Subtle embossing of text and icons for added contrast
• Connection of functional elements – viz. the tab to the titlebar, as opposed to Proton's disconnected floating tabs
• Gentle gradients and highlights

This userchrome is intended to be used with the Firefox Colors plugin and this theme but of course it'll look fine with a wide variety of colors.

If you find bugs or want to suggest improvements, feel free to open an issue or submit a pull request.

See what it looks like.

How to install

See also more detailed instructions.

1. Navigate to about:config
2. Search for the toolkit.legacyUserProfileCustomizations.stylesheets preference and set it to true
3. Create a folder called Chrome in your Firefox user profile folder and add these two CSS files
4. Restart Firefox

I also recommend setting the widget.non-native-theme.enabled preference to false to disable Firefox's custom widgets and use the native system widgets.