Edge-Frfox

A Firefox userChrome.css theme that aims to recreate the look and feel of the Chromium version of Microsoft Edge.

How to install

1. Go to about:support and click the "Open Folder/Show in Finder" button for the root directory of your browser profile/s.

2. Download and copy the chrome folder into the profile folder.

3. Go to about:config and change these preferences:

   For all operating systems:

   • toolkit.legacyUserProfileCustomizations.stylesheets = true
   • svg.context-properties.content.enabled = true
   • layout.css.color-mix.enabled = true

   Firefox 119.0 and above:

   • layout.css.light-dark.enabled = true

   On macOS:

   • To use the Edge style context menu on macOS then set widget.macos.native-context-menus = false

   Recommended:

   • browser.tabs.tabMinWidth = 66
   • browser.tabs.tabClipWidth = 86

   Optional:

   • To use the light theme in private browsing mode set browser.theme.dark-private-windows = false

   Additional tweaks can also be applied to the theme, such as Floating Tabs, rounded browser corners and more. See Tweaks.

Note: Most frequently tested on macOS

Screenshots

Theme	Light	Dark
Default (Windows 11)
Floating Tabs (Windows 11)
GTK (GNOME 42, adw-gtk3 theme)

Tweaks

Certain tweaks can be applied to the theme, to enable them navigate to about:config and create a boolean key for each tweak you want to use and set it to true, then restart the browser.

To disable a tweak, set the key to false or delete it, then restart the browser.

Enable Edge style floating tabs
uc.tweak.floating-tabs
OPTIONAL1: Make the top and bottom margins of the tab equal
uc.tweak.floating-tabs.equal-margin

Enable rounded corners
uc.tweak.rounded-corners

Hide Tabs Bar (Useful when using vertical tabs extensions such as Sidebery, Tree Style Tab, etc.)
NOTE: At the moment, this only supports macOS and Windows.
uc.tweak.hide-tabs-bar
OPTIONAL: Only enable in fullscreen mode (currently: macOS Only!)
uc.tweak.hide-tabs-bar.only-when-maximised

Use background image on newtab page
SETUP: Add an image named background-0.(jpg/png) to the chrome folder.
OPTIONAL: Add a second image named background-1.(jpg/png) for seperate dark mode background.
uc.tweak.newtab-background

Hide Firefox logo on newtab page
uc.tweak.hide-newtab-logo

Disable drag space above tabs
uc.tweak.disable-drag-space

Force tab background colour to the same colour as the navbar background (useful for Proton themes)
NOTE: can cause readability issues with some themes! (eg. white text on white bg)
uc.tweak.force-tab-colour
(Left: OFF, Right: ON)

Show context menu navigation buttons (Back, Forward, Reload, Bookmark) vertically
NOTE: labels are only shown in the English language.
uc.tweak.vertical-context-navigation

Remove tab separators
uc.tweak.remove-tab-separators

Use Firefox's default context menu font-size (only applies to Windows)
uc.tweak.smaller-context-menu-text

Disable custom context menus
uc.tweak.revert-context-menu

If a tab's close button is hidden, show it when hovering over tab
uc.tweak.show-tab-close-button-on-hover

Mica Tweak Notice

Mica is broken due to changes made in the Firefox 115 update, Mica has now been removed from this theme.

If you still have uc.tweak.win11-mica set in about:config you can safely delete it

Acknowledgements

muckSponge - MaterialFox

Microsoft - Fluent UI System Icons

KibSquib48 - MicaFox