diff --git a/core/modules/edit/lib/Drupal/edit/EditController.php b/core/modules/edit/lib/Drupal/edit/EditController.php
index da224bb..33544b3 100644
--- a/core/modules/edit/lib/Drupal/edit/EditController.php
+++ b/core/modules/edit/lib/Drupal/edit/EditController.php
@@ -126,7 +126,7 @@ public function fieldForm(EntityInterface $entity, $field_name, $langcode, $view
     }
 
     // When working with a hidden form, we don't want any CSS or JS to be loaded.
-    if (isset($_POST['nocssjs']) && $_POST['nocssjs'] === 'true') {
+    if (\Drupal::request()->request->get('nocssjs') === 'true') {
       drupal_static_reset('drupal_add_css');
       drupal_static_reset('drupal_add_js');
     }