--- a/toolkit/content/autocomplete.css
+++ b/toolkit/content/autocomplete.css
@@ -25,16 +25,16 @@ richlistitem {
   text-overflow: ellipsis;
   white-space: nowrap;
 }
 
 .ac-tags[empty] {
   display: none;
 }
 
-.ac-action[actiontype=searchengine]:not([selected]),
-.ac-separator[actiontype=searchengine]:not([selected]) {
+.autocomplete-richlistitem:not([selected]):not(:hover) > .ac-action[actiontype=searchengine],
+.autocomplete-richlistitem:not([selected]):not(:hover) > .ac-separator[actiontype=searchengine] {
   display: none;
 }
 
 .ac-separator[type=keyword] {
   display: none;
 }