userChrome.css

:root {
  --tnbp-highlight-color: #aeded6;
}

#nav-bar { /* main toolbar */
	-moz-box-ordinal-group: 1 !important;
	border-top-width: 0 !important;
}
#PersonalToolbar { /* bookmarks toolbar */
	-moz-box-ordinal-group: 2 !important;
}
#TabsToolbar { /* tab bar */
	-moz-box-ordinal-group: 3 !important;
}

/* Move the Open Menu, 3-bar button to the left & change its color */

#PanelUI-button {
	-moz-box-ordinal-group: 0 !important;
	color: orangered !important;
	border-left: none !important;
	position: absolute !important;
	padding-left: 0px !important;
	padding-right: 0px !important;
}

#PanelUI-menu-button {
	list-style-image: url("fxmenu.png") !important;
	margin-left: 5px !important;
}

#PanelUI-menu-button:hover {
	list-style-image: url("fxmenu_hover.png") !important;
	margin-left: 5px !important;
}

#PanelUI-menu-button > .toolbarbutton-badge-stack {
	background-color: #ffd080;
	border: 1px solid #d96300;
	/*margin-bottom: -10px; */
	height: 42px;
	width: 42px;
	padding-left: 12px !important;
	padding-top: 12px !important;
	padding-bottom: 12px !important;
	margin-top: 6px;
}

#PanelUI-menu-button:hover > .toolbarbutton-badge-stack {
	background-color: #ff7507 !important;
	border: 1px solid #d96300;
	/*margin-bottom: -10px; */
	height: 42px;
	width: 42px;
	padding-left: 12px !important;
	padding-top: 12px !important;
	padding-bottom: 12px !important;
	margin-top: 6px;
}

.tab-background {
	border-radius: 0px 0px !important;
	margin-bottom: 0px !important;
}

.tabbrowser-tab:not([selected=true]):not([multiselected=true]) .tab-background {
	background-color: color-mix(in srgb, currentColor 5%, transparent);
}

.tabbrowser-tab:not([selected=true]) label {
	color: color-mix(in srgb, currentColor 60%, transparent);
}

menupopup>menu,
menupopup>menuitem {
	padding-block: 2px !important;
}

:root {
	--arrowpanel-menuitem-padding: 2px !important;
}

#tabbrowser-arrowscrollbox {
	padding-left: 5px;
}

#nav-bar-customization-target {
	padding-left: 50px !important;
}

#unified-extensions-button {
	display: none;
}

#titlebar {
	background-color: InactiveCaption !important;
}

#alltabs-button image.toolbarbutton-icon:not(:-moz-window-inactive) {
	color: darkgray !important;
	fill: darkgray !important;
}

tab.tabbrowser-tab:not(:-moz-window-inactive) {
	color: rgb(49, 54, 59) !important;
}

tab.tabbrowser-tab:-moz-window-inactive {
	color: #7F7F7F !important;
}

#alltabs-button image.toolbarbutton-icon::-moz-window-inactive {
	color: gray !important;
	fill: gray !important;
}

#PanelUI-menu-button stack image {
	margin-top: -2px;
}

toolbarbutton.toolbarbutton-1:hover {
	color: rgb(49, 54, 59) !important;
}

#tabs-newtab-button {
	color: darkgray !important;
}

#tabs-newtab-button:hover {
	color: rgb(49, 54, 59) !important;
}

menu {
	color: rgb(49, 54, 59) !important;
}

menu:hover {
	background-color: ActiveCaption !important;
}

#downloads-button:not(:-moz-window-inactive) {
	color: rgb(49, 54, 59) !important;
}

#nav-bar-customization-target toolbaritem:last-of-type {
	margin-right: 1em !important;
}

#alltabs-button {
	display: none !important; /* fuck you. */
}

.tabbrowser-tab {
	height: 36px;
}

#TabsToolbar-customization-target {
	height: 38px;
}

#PersonalToolbar {
	z-index: 1 !important;
	border-top: 1px solid lightgray !important;
}

#appMenu-popup {
	position: absolute !important;
	margin-left: 250px !important;
	width: 250px;
}

#webext-perms-update-menu-item {
	display: none;
}

label.toolbarbutton-badge {
	display: none !important;
}

panelview#appMenu-mainView toolbarbutton:hover,
menupopup:not(#ContentSelectDropdownPopup) menuitem:not([disabled=true]):hover label,
menupopup:not(#ContentSelectDropdownPopup) menu:not([disabled=true]):hover span:first-of-type,
menupopup:not(#ContentSelectDropdownPopup) menu:not([disabled=true]):hover,
toolbarbutton.bookmark-item:hover,
#context-navigation menuitem:not([disabled=true]):hover,
#context-navigation menuitem:not([disabled=true]):hover img,
#nav-bar-customization-target toolbarbutton:not([disabled=true]):hover image,
#urlbar-results div:hover,
#downloads-button:hover .toolbarbutton-badge-stack,
#downloads-button:active .toolbarbutton-badge-stack,
#TabsToolbar-customization-target toolbaritem box toolbarbutton:hover stack,
box.unified-extensions-item-row-wrapper toolbarbutton:hover stack,
box.unified-extensions-item-row-wrapper toolbarbutton:hover stack image,
#tabs-newtab-button:hover image,
hbox.tab-content image.tab-close-button:hover,
#downloadsHistory:hover,
richlistitem:not([disabled=true]):hover,
#star-button-box:hover,
#tracking-protection-icon-container:hover,
#identity-box box:hover,
#main-button span.button-background:hover,
#PlacesChevron:hover,
#menuWebDeveloperPopup menuitem:hover,
#appmenu-developer-tools-view toolbarbutton:hover,
#appmenu-moreTools-button:hover,
toolbarbutton.subviewbutton:not([disabled=true]):hover {
	background-color: var(--tnbp-highlight-color) !important;
}

menupopup#contentAreaContextMenu {
	background-color: none !important;
}

.menupopup-arrowscrollbox {
	background-color: white;
}