Here is the CSS that I finally came to use. Not my creation. It puts Tabs under the Address bar (although they're a bit larger than I'd like), adjusts the Menu bar (if you use it) and puts a Status bar at the bottom (although it is still visible in Full Screen mode):
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/* Source file
https://github.com/MrOtherGuy/firefox-c ... bottom.css made available under Mozilla Public License v. 2.0
See the above repository for updates as well as full license text. */
/* Modify to change window drag space width */
/*
Use tabs_on_bottom_menubar_on_top_patch.css if you
have menubar permanently enabled and want it on top
*/
/* IMPORTANT */
/*
Get window_control_placeholder_support.css
Window controls will be all wrong without it.
Additionally on Linux, you may need to get:
linux_gtk_window_control_patch.css
*/
:root{ --uc-titlebar-padding: 0px; }
@media (-moz-os-version: windows-win7),(-moz-os-version: windows-win10){
:root[sizemode="maximized"][tabsintitlebar]{ --uc-titlebar-padding: 8px }
}
#toolbar-menubar[autohide="true"] > .titlebar-buttonbox-container,
#TabsToolbar > .titlebar-buttonbox-container{
position: fixed;
display: block;
top: var(--uc-titlebar-padding,0px);
right:0;
height: 40px;
}
/* Mac specific. You should set that font-smoothing pref to true if you are on any platform where window controls are on left */
@supports -moz-bool-pref("layout.css.osx-font-smoothing.enabled"){
:root{ --uc-titlebar-padding: 0px !important }
.titlebar-buttonbox-container{ left:0; right: unset !important; }
}
:root[uidensity="compact"] #TabsToolbar > .titlebar-buttonbox-container{ height: 32px }
#toolbar-menubar[inactive] > .titlebar-buttonbox-container{ opacity: 0 }
#navigator-toolbox{ padding-top: var(--uc-titlebar-padding,0px) !important; }
.titlebar-buttonbox-container > .titlebar-buttonbox{ height: 100%; }
#titlebar{
-moz-box-ordinal-group: 2;
-moz-appearance: none !important;
--tabs-navbar-shadow-size: 0px;
}
.titlebar-placeholder,
#TabsToolbar .titlebar-spacer{ display: none; }
/* Also hide the toolbox bottom border which isn't at bottom with this setup */
#navigator-toolbox::after{ display: none !important; }
@media (-moz-gtk-csd-close-button){ .titlebar-button{ -moz-box-orient: vertical } }
/* These exist only for compatibility with autohide-tabstoolbar.css */
toolbox#navigator-toolbox > toolbar#nav-bar.browser-toolbar{ animation: none; }
#navigator-toolbox:hover #TabsToolbar{ animation: slidein ease-out 48ms 1 }
/* Source file
https://github.com/MrOtherGuy/firefox-c ... _patch.css made available under Mozilla Public License v. 2.0
See the above repository for updates as well as full license text. */
/* Menubar on top patch - use with tabs_on_bottom.css */
/* Only really useful if menubar is ALWAYS visible */
:root:not([sizemode="fullscreen"]){ --uc-window-control-width: 0px !important }
:root{
/* height if native titlebar is enabled, assumes empty menubar */
--uc-menubar-height: 22px;
}
:root[tabsintitlebar]{
/* height when native titlebar is disabled, more roomy so can fit buttons etc. */
--uc-menubar-height: 22px;
}
#navigator-toolbox{ padding-top: calc(var(--uc-menubar-height) + var(--uc-titlebar-padding,0px)) !important }
:root[sizemode="fullscreen"] #navigator-toolbox{ padding-top: 0px !important; }
#toolbar-menubar{
position: fixed;
display: flex;
top: var(--uc-titlebar-padding,0px);
height: var(--uc-menubar-height);
width: 100%;
overflow: hidden;
}
#toolbar-menubar > .titlebar-buttonbox-container{ height: 100%; order: 100; }
#toolbar-menubar > [flex]{ flex-grow: 100; }
#toolbar-menubar > spacer[flex]{
order: 99;
flex-grow: 1;
min-width: var(--uc-window-drag-space-width,20px);
}
#toolbar-menubar .titlebar-button{ padding: 2px 17px !important; }
#toolbar-menubar .toolbarbutton-1 { --toolbarbutton-inner-padding: 3px }
/* Status-bar */
#browser-bottombox { height: 20px; border-top: solid 0px #505050; }
.browserContainer>statuspanel { left: 4px !important; bottom: 0px; transition-duration: 0s !important; transition-delay: 0s !important; }
.browserContainer>statuspanel>.statuspanel-inner>.statuspanel-label { margin-left: 0px !important; border: none !important; padding: 0px !important; }
window[inFullscreen="true"] #browser-bottombox { display:none !important; }
window[inFullscreen="true"] .browserContainer>statuspanel[type="overLink"] .statuspanel-label { display:none !important; }
#statuspanel #statuspanel-label {
-moz-appearance: none !important;
background-color: transparent !important;
border: 0px solid black !important;
}
#statuspanel {
background-color: transparent !important;
border: none !important;
bottom: 18px !important; /* adjust*/
height: 18px !important; /* adjust */
max-width: 30% !important; /* Change the value to suite your needs */
transition: none !important;
}
#PopupAutoCompleteRichResult {
display: none!important;
}}