diff --git a/core/modules/system/src/Controller/BatchController.php b/core/modules/system/src/Controller/BatchController.php
index 7975dcc..326dca9 100644
--- a/core/modules/system/src/Controller/BatchController.php
+++ b/core/modules/system/src/Controller/BatchController.php
@@ -66,7 +66,12 @@ public function batchPage(Request $request) {
         '#show_messages' => FALSE,
         'content' => $output,
       ];
-      return $page;
+
+      $html = [
+        '#type' => 'html',
+        'page' => $output,
+      ];
+      return $html;
     }
   }