diff --git a/theme/system-icons.css b/theme/system-icons.css
index 63819e9..123084b 100644
--- a/theme/system-icons.css
+++ b/theme/system-icons.css
@@ -70,6 +70,7 @@
 		list-style-image: url("moz-icon://stock/open-menu-symbolic?size=dialog") !important;
 	}
 	/* New tab button */
+	#new-tab-button .toolbarbutton-icon,
 	#tabs-newtab-button  .toolbarbutton-icon,
 	#TabsToolbar #new-tab-button .toolbarbutton-icon {
 		filter: var(--gnome-icons-hack-filter);