Added min-height in case of empty multi-select

core/css/multiselect.css

@@ -52,6 +52,7 @@ div.multiselect {
 	display: inline-block;
 	max-width: 400px;
 	min-width: 150px;
+	min-height: 20px;
 	padding-right: .6em;
 	position: relative;
 	vertical-align: bottom;