Firefox 65 on Windows 8.1: menu; navigation; tabs; content

userChrome.css

/* 

>>>> NOTE: buggy when dragging / re-ordering tabs.

With thanks to everyone on /r/FirefoxCSS, I have this: 

https://i.imgur.com/YE3s6gm.png

Firefox 65 on Windows 8.1, from the top:

Row 1: File Edit View History Bookmarks Tools Help (with vertically-middled alignment) <--> Min / Max / Close
Row 2: Navigation bar 
Row 3. Tabs 

*/

#navigator-toolbox {
  height:108px;
}

#main-menubar {
  height:30px;
}

#TabsToolbar {
  bottom: 0 !important;
  position: absolute !important;
}

#tabbrowser-tabs {
  min-height: 34px;
  width: 100vw !important;
}

/* 
 
Visual improvements that work with the toolbar order achieved above

*/

#nav-bar {
  box-shadow:unset !important;
}

/* 
 
Changes to suit my own needs

*/

#nav-bar #back-button, 
#nav-bar #forward-button,
#nav-bar #stop-reload-button {
  -moz-box-pack: center;
  width:5em;
}

#nav-bar #page-action-buttons,
#nav-bar #PanelUI-button {
   display:none;
}