personal userChrome.css

userChrome.css

/* Hides the top tabs bar */
#TabsToolbar { visibility: collapse !important; }
#titlebar { appearance: none !important }

/**
 * Decrease size of the sidebar header
 */
#sidebar-header {
  font-size: 1.2em !important;
  padding: 2px 6px 2px 3px !important;
}
#sidebar-header #sidebar-close {
  padding: 3px !important;
}
#sidebar-header #sidebar-close .toolbarbutton-icon {
  width: 14px !important;
  height: 14px !important;
  opacity: 0.6 !important;
}

/* Center personal bookmarks bar */
#PlacesToolbarItems {
    justify-content: center;
}

/* Hide Firefox Containers button in url bar */
hbox #pageAction-urlbar-_testpilot-containers{
    visibility: collapse !important;
}

/* Center url bar text when not in focus */
#urlbar:not([focused]) .urlbar-input{ 
    text-align: center !important; 
}

/* Hide sidebar menu */
#sidebar-header { display: none }

/* Change color of selection in url bar */
#urlbar-input::selection {
  background-color: #808080 !important;
}