--- a/browser/themes/osx/browser.css
+++ b/browser/themes/osx/browser.css
@@ -794,16 +794,17 @@ html|span.ac-emphasize-text-url {
 
 
 /* ----- SIDEBAR ELEMENTS ----- */
 
 %include ../shared/sidebar.inc.css
 
 #sidebar-box {
   -moz-appearance: -moz-mac-source-list;
+  -moz-font-smoothing-background-color: -moz-mac-source-list;
 }
 
 #sidebar-header {
   /* system font size is a bit smaller in mac, so need more ems. */
   font-size: 1.4545em;
   border-bottom: 1px solid hsla(240, 5%, 5%, .1);
   background-color: transparent;
 }
@@ -891,21 +892,26 @@ html|span.ac-emphasize-text-url {
 
 #TabsToolbar:not(:-moz-lwtheme) {
   color: #333;
   text-shadow: @loweredShadow@;
 }
 
 :root:-moz-any([inFullscreen], [tabsintitlebar]) #TabsToolbar:not(:-moz-lwtheme) {
   -moz-appearance: -moz-mac-vibrancy-dark;
+  -moz-font-smoothing-background-color: -moz-mac-vibrancy-dark;
   background-color: #232323;
   color: hsl(240, 9%, 98%);
   text-shadow: none;
 }
 
+.tabbrowser-tab[visuallyselected=true] {
+  -moz-font-smoothing-background-color: var(--toolbar-bgcolor);
+}
+
 #tabbrowser-tabs {
   -moz-box-align: stretch;
 }
 
 /**
  * Tab Drag and Drop
  */
 

--- a/browser/themes/osx/places/organizer.css
+++ b/browser/themes/osx/places/organizer.css
@@ -13,20 +13,22 @@
 
 #placesList > treechildren::-moz-tree-cell-text {
   font-size: 12px;
   margin-inline-end: 6px;
 }
 
 #placesList > treechildren::-moz-tree-row(selected) {  
   -moz-appearance: -moz-mac-source-list-selection;
+  -moz-font-smoothing-background-color: -moz-mac-source-list-selection;
 }
 
 #placesList > treechildren::-moz-tree-row(selected,focus) {  
   -moz-appearance: -moz-mac-active-source-list-selection;
+  -moz-font-smoothing-background-color: -moz-mac-active-source-list-selection;
 }
 
 #placesList > treechildren::-moz-tree-row(History),
 #placesList > treechildren::-moz-tree-row(history)  {
   background-color: blue;
 }
 
 #placesList > treechildren::-moz-tree-cell(separator) {

--- a/browser/themes/osx/places/places.css
+++ b/browser/themes/osx/places/places.css
@@ -16,33 +16,36 @@
   margin: 0;
   height: 24px;
   /* Default font size is 11px on mac, so this is 12px */
   font-size: 1.0909rem;
 }
 
 .sidebar-placesTree {
   -moz-appearance: -moz-mac-source-list;
+  -moz-font-smoothing-background-color: -moz-mac-source-list;
 }
 
 .sidebar-placesTreechildren::-moz-tree-separator {
   border-top: 1px solid #505d6d;
   margin: 0 10px;
 }
 
 .sidebar-placesTreechildren::-moz-tree-row {
   background-color: transparent;
 }
 
 .sidebar-placesTreechildren::-moz-tree-row(selected) {
   -moz-appearance: -moz-mac-source-list-selection;
+  -moz-font-smoothing-background-color: -moz-mac-source-list-selection;
 }
 
 .sidebar-placesTreechildren::-moz-tree-row(selected,focus) {
   -moz-appearance: -moz-mac-active-source-list-selection;
+  -moz-font-smoothing-background-color: -moz-mac-active-source-list-selection;
 }
 
 .sidebar-placesTreechildren::-moz-tree-cell-text {
   margin-inline-end: 6px;
 }
 
 .sidebar-placesTreechildren::-moz-tree-cell-text(selected) {
   color: #fff;

--- a/browser/themes/osx/syncedtabs/sidebar.css
+++ b/browser/themes/osx/syncedtabs/sidebar.css
@@ -3,16 +3,17 @@
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 
 %include ../../shared/syncedtabs/sidebar.inc.css
 
 /* These styles are intended to mimic XUL trees and the XUL search box. */
 
 .content-container {
   -moz-appearance: -moz-mac-source-list;
+  -moz-font-smoothing-background-color: -moz-mac-source-list;
 }
 
 .item {
   color: -moz-DialogText;
 }
 
 .item-title-container {
   box-sizing: border-box;
@@ -23,20 +24,22 @@
 
 .item.selected > .item-title-container {
   color: HighlightText;
   font-weight: bold;
 }
 
 .item.selected > .item-title-container {
   -moz-appearance: -moz-mac-source-list-selection;
+  -moz-font-smoothing-background-color: -moz-mac-source-list-selection;
 }
 
 .item.selected:focus > .item-title-container {
   -moz-appearance: -moz-mac-active-source-list-selection;
+  -moz-font-smoothing-background-color: -moz-mac-active-source-list-selection;
 }
 
 .item.client .item-twisty-container {
   min-width: 16px;
   height: 16px;
   background-image: url("chrome://global/skin/tree/arrow-disclosure.svg#arrow-disclosure-expanded");
 }
 

--- a/toolkit/themes/osx/global/menu.css
+++ b/toolkit/themes/osx/global/menu.css
@@ -101,16 +101,17 @@ menubar > menu {
 
 menubar > menu[_moz-menuactive="true"] {
   color: inherit;
   background-color: transparent;
 }
 
 menubar > menu[_moz-menuactive="true"][open="true"] {
   -moz-appearance: menuitem;
+  -moz-font-smoothing-background-color: -moz-mac-active-menuitem;
   color: -moz-mac-menutextselect;
 }
 
 /* ..... internal content .... */
 
 .menubar-left {
   margin: 0 2px;
   color: inherit;
@@ -126,16 +127,17 @@ menubar > menu[_moz-menuactive="true"][o
 menupopup > menu,
 menupopup > menuitem,
 menupopup > menucaption {
   max-width: 42em;
 }
 
 menu[_moz-menuactive="true"],
 menuitem[_moz-menuactive="true"] {
+  -moz-font-smoothing-background-color: -moz-mac-active-menuitem;
   color: -moz-mac-menutextselect;
   background-color: Highlight;
 }
 
 menuitem[customoptionstyling="true"] {
   -moz-appearance: none;
   padding-top: 0;
   padding-bottom: 0;

--- a/toolkit/themes/osx/global/popup.css
+++ b/toolkit/themes/osx/global/popup.css
@@ -2,16 +2,17 @@
  * License, v. 2.0. If a copy of the MPL was not distributed with this
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 
 @namespace url("http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul");
 
 menupopup,
 panel {
   -moz-appearance: menupopup;
+  -moz-font-smoothing-background-color: -moz-mac-menupopup;
   background-color: Menu;
 }
 
 menupopup > menu > menupopup {
   margin-top: -4px;
 }
 
 .popup-internal-box {
@@ -97,16 +98,17 @@ panel[type="arrow"][side="right"] {
     height: 18px;
   }
 }
 
 /* ::::: tooltip ::::: */
 
 tooltip {
   -moz-appearance: tooltip;
+  -moz-font-smoothing-background-color: -moz-mac-tooltip;
   margin-top: 18px;
   padding: 2px 3px;
   max-width: 40em;
   color: InfoText;
   font: message-box;
   cursor: default;
 }