diff --git a/src/wp-includes/css/admin-bar.css b/src/wp-includes/css/admin-bar.css
index 533fa8216a..c27821d60d 100644
--- a/src/wp-includes/css/admin-bar.css
+++ b/src/wp-includes/css/admin-bar.css
@@ -142,6 +142,10 @@
 	left: 0;
 }
 
+#wpadminbar .ab-top-menu > .menupop > .ab-sub-wrapper {
+	min-width: 100%;
+}
+
 #wpadminbar .ab-top-secondary .menupop .ab-sub-wrapper {
 	right: 0;
 	left: auto;