diff --git a/toolkit/themes/shared/close-icon.inc.css b/toolkit/themes/shared/close-icon.inc.css
index 2958b62f0b61..3698a4ea4c73 100644
--- a/toolkit/themes/shared/close-icon.inc.css
+++ b/toolkit/themes/shared/close-icon.inc.css
@@ -19,7 +19,6 @@
   fill-opacity: 0.2;
 }
 
-image.close-icon,
 .close-icon > .button-icon,
 .close-icon > .button-box > .button-icon,
 .close-icon > .toolbarbutton-icon {