diff --git a/core/modules/field_ui/lib/Drupal/field_ui/FieldInstanceListController.php b/core/modules/field_ui/lib/Drupal/field_ui/FieldInstanceListController.php
index b7c9048..c7ad5ce 100644
--- a/core/modules/field_ui/lib/Drupal/field_ui/FieldInstanceListController.php
+++ b/core/modules/field_ui/lib/Drupal/field_ui/FieldInstanceListController.php
@@ -141,7 +141,10 @@ public function load() {
   public function buildHeader() {
     $header = array(
       'label' => $this->t('Label'),
-      'machine_name' => $this->t('Machine name'),
+      'machine_name' => array(
+        'data' => $this->t('Machine name'),
+        'class' => array(RESPONSIVE_PRIORITY_MEDIUM),
+      ),
       'field_type' => $this->t('Field type'),
     );
     return $header + parent::buildHeader();