diff --git a/core/modules/file/file.module b/core/modules/file/file.module
index efd4afb..eb900d9 100644
--- a/core/modules/file/file.module
+++ b/core/modules/file/file.module
@@ -58,6 +58,7 @@ function file_help($route_name, RouteMatchInterface $route_match) {
 function file_element_info() {
   $types['managed_file'] = array(
     '#input' => TRUE,
+    '#value_callback' => '\Drupal\file\Element\ManagedFile::valueCallback',
     '#process' => array(
       '\Drupal\file\Element\ManagedFile::processManagedFile',
     ),