diff --git a/toolkit/themes/linux/global/autocomplete.css b/toolkit/themes/linux/global/autocomplete.css
index 4f6f21f636e1..c3010359d00d 100644
--- a/toolkit/themes/linux/global/autocomplete.css
+++ b/toolkit/themes/linux/global/autocomplete.css
@@ -17,8 +17,7 @@ textbox[nomatch="true"][highlightnonmatches="true"] {
 
 /* ::::: autocomplete popups ::::: */
 
-panel[type="autocomplete-richlistbox"],
-.autocomplete-history-popup {
+panel[type="autocomplete-richlistbox"] {
   border: 1px solid ThreeDShadow;
   padding: 0;
   color: -moz-FieldText;
@@ -26,10 +25,6 @@ panel[type="autocomplete-richlistbox"],
   -moz-appearance: none;
 }
 
-.autocomplete-history-popup {
-  max-height: 180px;
-}
-
 /* ::::: richlistbox autocomplete ::::: */
 
 .autocomplete-richlistbox {
diff --git a/toolkit/themes/linux/global/menu.css b/toolkit/themes/linux/global/menu.css
index 87e15c9386d1..299d18164243 100644
--- a/toolkit/themes/linux/global/menu.css
+++ b/toolkit/themes/linux/global/menu.css
@@ -185,10 +185,3 @@ menuitem[type="radio"] {
 menuseparator {
   -moz-appearance: menuseparator;
 }
-
-/* ::::: autocomplete ::::: */
-
-.autocomplete-history-popup > menuitem {
-  max-width: none !important;
-  font: message-box;
-}
diff --git a/toolkit/themes/osx/global/autocomplete.css b/toolkit/themes/osx/global/autocomplete.css
index 4704671a78f7..033b6d492b39 100644
--- a/toolkit/themes/osx/global/autocomplete.css
+++ b/toolkit/themes/osx/global/autocomplete.css
@@ -11,8 +11,7 @@ textbox[nomatch="true"][highlightnonmatches="true"] {
 
 /* ::::: autocomplete popups ::::: */
 
-panel[type="autocomplete-richlistbox"],
-.autocomplete-history-popup {
+panel[type="autocomplete-richlistbox"] {
   padding: 0px !important;
   color: -moz-FieldText;
   background-color: -moz-Field;
@@ -20,10 +19,6 @@ panel[type="autocomplete-richlistbox"],
   -moz-appearance: none;
 }
 
-.autocomplete-history-popup {
-  max-height: 180px;
-}
-
 /* ::::: richlistbox autocomplete ::::: */
 
 .autocomplete-richlistbox {
diff --git a/toolkit/themes/osx/global/menu.css b/toolkit/themes/osx/global/menu.css
index 6cb21064179e..9ab4a8a12725 100644
--- a/toolkit/themes/osx/global/menu.css
+++ b/toolkit/themes/osx/global/menu.css
@@ -177,10 +177,3 @@ menuseparator {
   margin: 5px 0;
   padding: 1px 0;
 }
-
-/* ::::: autocomplete ::::: */
-
-.autocomplete-history-popup > menuitem {
-  max-width: none !important;
-  font: message-box;
-}
diff --git a/toolkit/themes/windows/global/autocomplete.css b/toolkit/themes/windows/global/autocomplete.css
index 76b30d55f834..b515ce217ba5 100644
--- a/toolkit/themes/windows/global/autocomplete.css
+++ b/toolkit/themes/windows/global/autocomplete.css
@@ -17,18 +17,13 @@ textbox[nomatch="true"][highlightnonmatches="true"] {
 
 /* ::::: autocomplete popups ::::: */
 
-panel[type="autocomplete-richlistbox"],
-.autocomplete-history-popup {
+panel[type="autocomplete-richlistbox"] {
   -moz-appearance: none;
   padding: 0;
   color: -moz-FieldText;
   background-color: -moz-Field;
 }
 
-.autocomplete-history-popup {
-  max-height: 180px;
-}
-
 /* ::::: richlistbox autocomplete ::::: */
 
 .autocomplete-richlistbox {
diff --git a/toolkit/themes/windows/global/menu.css b/toolkit/themes/windows/global/menu.css
index 963c8aa2a4b3..d4c37d682920 100644
--- a/toolkit/themes/windows/global/menu.css
+++ b/toolkit/themes/windows/global/menu.css
@@ -269,10 +269,3 @@ menulist > menupopup > menuseparator {
   border-top: 1px solid #000000;
   border-bottom: none;
 }
-
-/* ::::: autocomplete ::::: */
-
-.autocomplete-history-popup > menuitem {
-  max-width: none !important;
-  font: message-box;
-}