FoxOne

One-line layout, clean URL bar, hover-reveal icons, floating Findbar, Gruvbox colors and ready for Nova

Tested on Firefox 152+ with browser.nova.enabled and on Windows, macOS, and Linux (GNOME & KDE).

Running classic (pre-Nova) Firefox?

From release 3.0 onward, FoxOne targets the Nova UI. The stylesheet is dual-written (Proton & Nova) and should still work, but it is no longer tested. For a known-good classic build, use the 2.3 release.

Features

Dynamic URL bar with hover-reveal Icons

Dynamic tabs and two addons pinned by the hamburger, revealed on hover.

Floating Find Bar. Adapted from LittleFox

Installation

1. Download userChrome.css and userContent.css

2. Go to about:config in FireFox. Search for toolkit.legacyUserProfileCustomizations.stylesheets and set it to true.

3. Find your profile folder: In Firefox, go to about:support and click Open Profile Folder.

4. Create a chrome folder inside your profile folder if it doesn't exist, then copy these files into it:

• userChrome.css - browser UI styling
• userContent.css - new tab / home page colors

5. Restart Firefox - The theme applies on restart.

6. FoxOne includes a built-in Gruvbox inspired Dark color theme that activates automatically in dark mode. No separate extension needed.

Customisation

FoxOne is fully configurable through CSS variables. See all options → docs/customisation.md

Thunderbird?

You are looking for BirdOne!

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Installation and Customisation | Inspired by Cascade & LittleFox | It works with Adaptive Tab Bar Colour! | License: MIT