fix

ui/src/core/ui/form_builder/form_builder.tsx

@@ -1,4 +1,3 @@
-// @ts-nocheck
 import * as React from "react";
 import {
   FormViewModel,
@@ -223,7 +222,7 @@ export const FormBuilder = observer((props: IFormBuilder) => {
                   )}
                 </>
               );
-            return <>Error {element}</>;
+            return <div>Error {String(element)}</div>;
           })}
         </div>
       )}