--- a/browser/themes/shared/searchbar.inc.css
+++ b/browser/themes/shared/searchbar.inc.css
@@ -110,19 +110,19 @@
 
 .searchbar-engine-one-off-item:not([selected]):not(.dummy):hover,
 .addengine-item:hover {
   background-color: var(--arrowpanel-dimmed-further);
   color: inherit;
 }
 
 .searchbar-engine-one-off-item[selected] {
-  background-color: Highlight;
+  background-color: var(--autocomplete-popup-highlight-background);
   background-image: none;
-  color: HighlightText;
+  color: var(--autocomplete-popup-highlight-color);
 }
 
 .searchbar-engine-one-off-item > .button-box {
   padding: 0;
 }
 
 .searchbar-engine-one-off-item > .button-box > .button-text {
   display: none;
@@ -147,18 +147,18 @@
   padding: 0 10px;
 }
 
 .addengine-item:first-of-type {
   border-top: 1px solid var(--panel-separator-color);
 }
 
 .addengine-item[selected] {
-  background-color: Highlight;
-  color: HighlightText;
+  background-color: var(--autocomplete-popup-highlight-background);
+  color: var(--autocomplete-popup-highlight-color);
 }
 
 .addengine-item[type=menu][selected] {
   color: inherit;
   background-color: var(--arrowpanel-dimmed-further);
 }
 
 .addengine-item > .toolbarbutton-badge-stack > .toolbarbutton-icon {