legacy/proton/non_active_tab_shape.css
/* Firefox Proton userChrome.css tweaks *********************************************************/
/* Github: https://github.com/aris-t2/customcssforfx ********************************************/
/************************************************************************************************/


/* 'Real compact' Proton UI for userChrome.css

### HOWTO ###

1. Open profile folder: address bar > about:support > Profile Folder > Open Folder
   Create "chrome" (sub)folder.
   Save this file as 'userChrome.css' inside "chrome" folder or add code to an existing userChrome.css file.

2. Open config area: address bar > about:config > modify/add the following values/settings:

   toolkit.legacyUserProfileCustomizations.stylesheets > true   ||  enables custom style sheets
   browser.compactmode.show > true   ||  shows 'Compact mode' in customizing mode 
   browser.uidensity > 1   ||  enables compact mode
   browser.proton.enabled > true   ||  enables proton mode
   browser.proton.contextmenus.enabled   ||  enables proton context menus
   browser.proton.doorhangers.enabled > true
   browser.proton.modals.enabled > true
   browser.proton.places-tooltip.enabled > true

3. Restart browser

*/


@supports -moz-bool-pref("browser.proton.enabled") {
	
.tabbrowser-tab:not(:hover) > .tab-stack > .tab-background:not([selected=true], [multiselected]) {
  background-color: color-mix(in srgb, currentColor 11%, transparent);
}

.tabbrowser-tab:hover > .tab-stack > .tab-background:not([selected=true], [multiselected]) {
  background-color: color-mix(in srgb, currentColor 17%, transparent) !important;
}

}