Deciare's Firefox CSS hacks

A collection customisations to Firefox and Sidebery implemented via userChrome.css and Sidebery's built-in Style Editor.

Setting up userChrome.css

Refer to https://www.reddit.com/r/FirefoxCSS/comments/73dvty/tutorial_how_to_create_and_livedebug_userchromecss/ for a guide on how to set up userChrome.css with live debugging.

Modules

This repository is set up as a collection of modules that can be independently enabled by importing them into userChrome.css. For example, the following lines in userChrome.css will enable the toolbar vibrancy effect on macOS and move tab close buttons to the left:

@import url(firefox/macVibrantToolbars.css);
@import url(firefox/tabCloseButtonOnLeft.css);

hideTabBar.css

Hides the tab bar. Best used with a vertical tabs extension such as Sidebery or Tree Style Tab.

Working as of Firefox 126.

macVibrantToolbars.css

On macOS, enables a vibrancy effect on the tab toolbar, navigation bar, and bookmarks toolbar.

You must also enable the following preferences in about:config:

• browser.theme.macos.native-theme
• widget.macos.titlebar-blend-mode.behind-window

Working as of Firefox 126.

tabCloseButtonOnLeft.css

Moves the tab close buttons to the left side of each tab. When the pointer hovers over a tab, the tab's favicon is replaced with a close button.

Working as of Firefox 120.

sideberyMods.css

Causes the Sidebery sidebar to auto-hide on the left edge of the browser window.

For this module to work well, see also sidebery/sidebar.css.

Based on Redundakitties/colorful-minimalist.

Working as of Firefox 120 and Sidebery 5.

sideberyModsOnRight.css

Requires sideberyMods.css to also be enabled. Causes the Sidebery sidebar to auto-hide on the right edge of the browser window instead of the left.

Working as of Firefox 120 and Sidebery 5.

sidebery/sidebar.css

Adjusts styling in Sidebery to work better with sideberyMods.css, and adds some optional behaviours.

To apply this stylesheet, copy and paste it into Sidebery's built-in styles editor. To access the style editor, open Sideberry Settings -> Styles editor.

Comment or uncomment sections within the styles editor to disable or enable optional behaviours.

• Spaces elements further apart when Appearance -> Density is set to "relaxed", to accommodate a collapsed width of up to 42px.
• Move tab close buttons to the left when close buttons are set to show "on mouse hover".
• Move tab container indicators to the left, so that they are visible when auto-hiding on the right.