Ticket #36521: 35612.1.diff

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

@@ -1796 +1796 @@
 
                         control.setting.bind( function( value ) {
 
+                                 var attachmentNeedsUpdating = control.params.attachment.id != value;
+
                                 // Send attachment information to the preview for possible use in `postMessage` transport.
                                 wp.media.attachment( value ).fetch().done( function() {
                                         wp.customize.previewer.send( control.setting.id + '-attachment-data', this.attributes );
+
+                                        if ( attachmentNeedsUpdating ) {
+                                                control.params.attachment = this.attributes;
+                                                control.renderContent();
+                                        }
                                 } );
 
-                                // Re-render whenever the control's setting changes.
-                                control.renderContent();
+                                if ( ! value ) {
+                                        control.params.attachment = {};
+                                }
+
+                                if ( ! attachmentNeedsUpdating || ! value ) {
+                                        // Re-render whenever the control's setting changes.
+                                        control.renderContent();
+                                }
                         } );
                 },