diff --git a/core/modules/menu/lib/Drupal/menu/MenuFormController.php b/core/modules/menu/lib/Drupal/menu/MenuFormController.php
index c51678f..8bc550f 100644
--- a/core/modules/menu/lib/Drupal/menu/MenuFormController.php
+++ b/core/modules/menu/lib/Drupal/menu/MenuFormController.php
@@ -22,6 +22,7 @@ public function form(array $form, array &$form_state, EntityInterface $menu) {
     $form = parent::form($form, $form_state, $menu);
     $system_menus = menu_list_system_menus();
     $form_state['menu'] = &$menu;
+    $is_custom_menu = !isset($system_menus[$menu->id()]);

     $form['label'] = array(
       '#type' => 'textfield',
@@ -29,7 +30,7 @@ public function form(array $form, array &$form_state, EntityInterface $menu) {
       '#default_value' => $menu->label(),
       '#required' => TRUE,
       // The title of a system menu cannot be altered.
-      '#access' => !isset($system_menus[$menu->id()]),
+      '#access' => $is_custom_menu,
     );
     $form['id'] = array(
       '#type' => 'machine_name',
@@ -45,6 +46,8 @@ public function form(array $form, array &$form_state, EntityInterface $menu) {
       ),
       // A menu's machine name cannot be changed.
       '#disabled' => !$menu->isNew() || isset($system_menus[$menu->id()]),
+      // The machine name of a system menu cannot be altered.
+      '#access' => $is_custom_menu,
     );
     $form['description'] = array(
       '#type' => 'textarea',