diff --git a/core/modules/forum/forum.routing.yml b/core/modules/forum/forum.routing.yml
index 13eb837..a5573d0 100644
--- a/core/modules/forum/forum.routing.yml
+++ b/core/modules/forum/forum.routing.yml
@@ -13,13 +13,13 @@ forum_settings:
 forum_add_container:
   pattern: 'admin/structure/forum/add/container'
   defaults:
-    _controller: 'Drupal\forum\ForumController::addContainer'
+    _content: 'Drupal\forum\ForumController::addContainer'
   requirements:
     _permission: 'administer forums'
 forum_add_forum:
   pattern: 'admin/structure/forum/add/forum'
   defaults:
-    _controller: 'Drupal\forum\ForumController::addForum'
+    _content: 'Drupal\forum\ForumController::addForum'
   requirements:
     _permission: 'administer forums'
 forum_edit_container:
diff --git a/core/modules/forum/lib/Drupal/forum/ContainerFormController.php b/core/modules/forum/lib/Drupal/forum/ContainerFormController.php
index 62c6af0..24dbd1d 100644
--- a/core/modules/forum/lib/Drupal/forum/ContainerFormController.php
+++ b/core/modules/forum/lib/Drupal/forum/ContainerFormController.php
@@ -41,9 +41,9 @@ public function form(array $form, array &$form_state) {
    * {@inheritdoc}
    */
   public function save(array $form, array &$form_state) {
-    $insert = $this->entity->isNew();
+    $is_new = $this->entity->isNew();
     $term = parent::save($form, $form_state);
-    if ($insert) {
+    if ($is_new) {
       // Update config item to track the container terms.
       $containers = $this->config->get('containers');
       $containers[] = $term->id();
diff --git a/core/modules/forum/lib/Drupal/forum/ForumFormController.php b/core/modules/forum/lib/Drupal/forum/ForumFormController.php
index 4bce670..37822ed 100644
--- a/core/modules/forum/lib/Drupal/forum/ForumFormController.php
+++ b/core/modules/forum/lib/Drupal/forum/ForumFormController.php
@@ -8,6 +8,7 @@
 namespace Drupal\forum;
 
 use Drupal\taxonomy\TermFormController;
+use Drupal\Core\Config\ConfigFactory;
 use Drupal\Core\Entity\EntityControllerInterface;
 use Symfony\Component\DependencyInjection\ContainerInterface;