set higher z-index for menu options (#28352)

editor/css/main.css

@@ -368,6 +368,7 @@ select {
 
 		#menubar .menu .options {
 			position: fixed;
+			z-index: 1; /* higher than resizer */
 			display: none;
 			padding: 5px 0;
 			background: #eee;