Ticket #37890: 37890.patch

src/wp-includes/class-wp-customize-manager.php

@@ -1012 +1012 @@
                                         $error_data = array();
                                 }
                                 $error_data = array_merge(
-                                        $error_data,
+                                        (array) $error_data,
                                         array( 'from_server' => true )
                                 );
                                 $notification[ $error_code ] = array(