--- a/browser/themes/shared/browser.inc.css
+++ b/browser/themes/shared/browser.inc.css
@@ -65,28 +65,30 @@
 }
 
 #library-animatable-box[animate] {
   display: -moz-box;
 }
 
 /* Back / Forward context menu */
 
+.unified-nav-back,
+.unified-nav-forward {
+  -moz-context-properties: fill;
+  fill: currentColor;
+}
+
 .unified-nav-back[_moz-menuactive]:-moz-locale-dir(ltr),
 .unified-nav-forward[_moz-menuactive]:-moz-locale-dir(rtl) {
   list-style-image: url("chrome://browser/skin/back.svg") !important;
-  -moz-context-properties: fill;
-  fill: currentColor;
 }
 
 .unified-nav-forward[_moz-menuactive]:-moz-locale-dir(ltr),
 .unified-nav-back[_moz-menuactive]:-moz-locale-dir(rtl) {
   list-style-image: url("chrome://browser/skin/forward.svg") !important;
-  -moz-context-properties: fill;
-  fill: currentColor;
 }
 
 /* Private browsing and accessibility indicators */
 
 .accessibility-indicator,
 .private-browsing-indicator {
   background-repeat: no-repeat;
   background-size: 100% auto;