diff --git a/wp-includes/css/admin-bar.dev.css b/wp-includes/css/admin-bar.dev.css
index 947c4635d..e0cc5945b 100644
--- a/wp-includes/css/admin-bar.dev.css
+++ b/wp-includes/css/admin-bar.dev.css
@@ -128,6 +128,10 @@
 	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;
@@ -209,6 +213,8 @@
 	background: #fff;
 	color: #333;
 	text-shadow: none;
+	border-right-color: transparent;
+	border-left-color: transparent;
 }
 
 #wpadminbar .hover .ab-label,