diff --git a/core/modules/views/views_ui/lib/Drupal/views_ui/ViewFormControllerBase.php b/core/modules/views/views_ui/lib/Drupal/views_ui/ViewFormControllerBase.php
index 772eecd..f05f0de 100644
--- a/core/modules/views/views_ui/lib/Drupal/views_ui/ViewFormControllerBase.php
+++ b/core/modules/views/views_ui/lib/Drupal/views_ui/ViewFormControllerBase.php
@@ -28,7 +28,9 @@
    * Overrides \Drupal\Core\Entity\EntityFormController::build().
    */
   public function build(array $form, array &$form_state, EntityInterface $entity) {
-    $this->displayID = $form_state['display_id'];
+    if (isset($form_state['display_id'])) {
+      $this->displayID = $form_state['display_id'];
+    }
 
     // @todo Remove the need for this.
     form_load_include($form_state, 'inc', 'views_ui', 'admin');