diff --git a/core/modules/comment/comment.services.yml b/core/modules/comment/comment.services.yml
index ec127e5..5a8051d 100644
--- a/core/modules/comment/comment.services.yml
+++ b/core/modules/comment/comment.services.yml
@@ -13,4 +13,4 @@ services:
 
   comment.manager:
     class: Drupal\comment\CommentManager
-    arguments: ['@field.info', '@entity.manager']
+    arguments: ['@field.info', '@entity.manager', '@database', '@module_handler', '@current_user']
diff --git a/core/modules/comment/lib/Drupal/comment/CommentManager.php b/core/modules/comment/lib/Drupal/comment/CommentManager.php
index 35f723c..6d59775 100644
--- a/core/modules/comment/lib/Drupal/comment/CommentManager.php
+++ b/core/modules/comment/lib/Drupal/comment/CommentManager.php
@@ -10,6 +10,9 @@
 use Drupal\Component\Utility\String;
 use Drupal\field\FieldInfo;
 use Drupal\Core\Entity\EntityManager;
+use Drupal\Core\Extension\ModuleHandlerInterface;
+use Drupal\Core\Database\Connection;
+use Drupal\Core\Session\AccountInterface;
 
 /**
  * Comment manager contains common functions to manage comment fields.
@@ -31,6 +34,27 @@ class CommentManager {
   protected $entityManager;
 
   /**
+   * Database connection
+   *
+   * @var \Drupal\Core\Database\Connection
+   */
+  protected $connection;
+
+  /**
+   * The module handler.
+   *
+   * @var \Drupal\Core\Extension\ModuleHandlerInterface
+   */
+  protected $moduleHandler;
+
+  /**
+   * The current user service.
+   *
+   * @var \Drupal\Core\Session\AccountInterface
+   */
+  protected $currentUser;
+
+  /**
    * Construct the CommentManager object.
    *
    * @param \Drupal\field\FieldInfo $field_info
@@ -38,9 +62,12 @@ class CommentManager {
    * @param \Drupal\Core\Entity\EntityManager $entity_manager
    *   The entity manager service.
    */
-  public function __construct(FieldInfo $field_info, EntityManager $entity_manager) {
+  public function __construct(FieldInfo $field_info, EntityManager $entity_manager, Connection $connection, ModuleHandlerInterface $module_handler, AccountInterface $current_user) {
     $this->fieldInfo = $field_info;
     $this->entityManager = $entity_manager;
+    $this->connection = $connection;
+    $this->moduleHandler = $module_handler;
+    $this->currentUser = $current_user;
   }
 
   /**
@@ -244,8 +271,6 @@ public function getFieldUIPageTitle($field_name) {
   /**
    * Returns the number of new comments for an user and the specified entity.
    *
-   * @todo Help, this uses procedural code! We've to get rid of that.
-   *
    * @param int $entity_id
    *   Entity ID of the entity to which the comments are attached.
    * @param string $entity_type
@@ -260,9 +285,7 @@ public function getFieldUIPageTitle($field_name) {
    *   The number of new comments or FALSE if the user is not logged in.
    */
   public function countNewComments($entity_id, $entity_type, $field_name = NULL, $timestamp = 0) {
-    $user = \Drupal::currentUser();
-
-    if ($user->isAuthenticated() && \Drupal::moduleHandler()->moduleExists('history')) {
+    if ($this->currentUser->isAuthenticated() && $this->moduleHandler->moduleExists('history')) {
       // Retrieve the timestamp when the current user last viewed this entity.
       if (!$timestamp) {
         if ($entity_type == 'node') {
@@ -283,7 +306,7 @@ public function countNewComments($entity_id, $entity_type, $field_name = NULL, $
       $timestamp = ($timestamp > HISTORY_READ_LIMIT ? $timestamp : HISTORY_READ_LIMIT);
 
       // Use the timestamp to retrieve the number of new comments.
-      $query = db_select('comment', 'c');
+      $query = $this->connection->select('comment', 'c');
       $query->addExpression('COUNT(cid)');
       $query->condition('c.entity_type', $entity_type)
         ->condition('c.entity_id', $entity_id)
@@ -301,4 +324,5 @@ public function countNewComments($entity_id, $entity_type, $field_name = NULL, $
       return FALSE;
     }
   }
+
 }
diff --git a/core/modules/forum/forum.services.yml b/core/modules/forum/forum.services.yml
index 8ea4dac..ea5cba1 100644
--- a/core/modules/forum/forum.services.yml
+++ b/core/modules/forum/forum.services.yml
@@ -1,7 +1,7 @@
 services:
   forum_manager:
     class: Drupal\forum\ForumManager
-    arguments: ['@config.factory', '@plugin.manager.entity', '@database', '@field.info', '@string_translation']
+    arguments: ['@config.factory', '@plugin.manager.entity', '@database', '@field.info', '@string_translation', '@comment.manager']
   forum.breadcrumb:
     class: Drupal\forum\ForumBreadcrumbBuilder
     arguments: ['@entity.manager', '@config.factory', '@forum_manager']
diff --git a/core/modules/forum/lib/Drupal/forum/ForumManager.php b/core/modules/forum/lib/Drupal/forum/ForumManager.php
index 0b42def..6564d36 100644
--- a/core/modules/forum/lib/Drupal/forum/ForumManager.php
+++ b/core/modules/forum/lib/Drupal/forum/ForumManager.php
@@ -11,6 +11,7 @@
 use Drupal\Core\Database\Connection;
 use Drupal\Core\Entity\EntityManager;
 use Drupal\Core\StringTranslation\TranslationInterface;
+use Drupal\comment\CommentManager;
 use Drupal\field\FieldInfo;
 use Drupal\node\NodeInterface;
 
@@ -61,6 +62,13 @@ class ForumManager implements ForumManagerInterface {
   protected $connection;
 
   /**
+   * The comment manager service.
+   *
+   * @var \Drupal\comment\CommentManager
+   */
+  protected $commentManager;
+
+  /**
    * Array of last post information keyed by forum (term) id.
    *
    * @var array
@@ -123,12 +131,13 @@ class ForumManager implements ForumManagerInterface {
    * @param \Drupal\Core\StringTranslation\TranslationInterface $translation_manager
    *   The translation manager service.
    */
-  public function __construct(ConfigFactory $config_factory, EntityManager $entity_manager, Connection $connection, FieldInfo $field_info, TranslationInterface $translation_manager) {
+  public function __construct(ConfigFactory $config_factory, EntityManager $entity_manager, Connection $connection, FieldInfo $field_info, TranslationInterface $translation_manager, CommentManager $comment_manager) {
     $this->configFactory = $config_factory;
     $this->entityManager = $entity_manager;
     $this->connection = $connection;
     $this->fieldInfo = $field_info;
     $this->translationManager = $translation_manager;
+    $this->commentManager = $comment_manager;
   }
 
   /**
@@ -312,7 +321,7 @@ protected function getTopicOrder($sortby) {
    *   Number of new comments.
    */
   protected function numberNew($nid, $timestamp) {
-    return \Drupal::service('comment.manager')->countNewComments($nid, 'node', 'comment_forum', $timestamp);
+    return $this->commentManager->countNewComments($nid, 'node', 'comment_forum', $timestamp);
   }
 
   /**