Ticket #32662: 32662.2.diff

src/wp-admin/css/customize-nav-menus.css

@@ -451 +451 @@
 .reordering .menu-item-depth-10 > .menu-item-bar { margin-right: 150px; }
 .reordering .menu-item-depth-11 > .menu-item-bar { margin-right: 165px; }
 
+/* Forces top margin to be zero for new menu */
+.control-section-nav_menu.open .menu {
+        margin-top: 0 !important;
+}
+
 .control-section-nav_menu .menu .menu-item-edit-active {
         margin-left: 0;
 }

src/wp-admin/js/customize-controls.js

@@ -605 +605 @@
                                                 overlay.addClass( 'section-open' );
                                                 position = content.offset().top;
                                                 scroll = container.scrollTop();
-                                                content.css( 'margin-top', ( 45 - position - scroll ) );
+                                                content.css( 'margin-top', ( $( '#customize-header-actions' ).height() - position - scroll ) );
                                                 if ( args.completeCallback ) {
                                                         args.completeCallback();
                                                 }