diff -u b/core/modules/comment/src/CommentManager.php b/core/modules/comment/src/CommentManager.php
--- b/core/modules/comment/src/CommentManager.php
+++ b/core/modules/comment/src/CommentManager.php
@@ -60,11 +60,11 @@
   protected $currentUser;
 
   /**
-   * History read limit time.
+   * History mark read time.
    *
    * @var int
    */
-  protected $historyReadLimit;
+  protected $historyMarkRead;
 
   /**
    * Construct the CommentManager object.
@@ -89,7 +89,7 @@
     $this->urlGenerator = $url_generator;
     $this->moduleHandler = $module_handler;
     $this->currentUser = $current_user;
-    $this->historyReadLimit = REQUEST_TIME - $config_factory->get('history.settings')->get('history_mark_read');
+    $this->historyMarkRead = $config_factory->get('history.settings')->get('history_mark_read');
   }
 
   /**
@@ -206,7 +206,8 @@
           }
         }
       }
-      $timestamp = ($timestamp > $this->historyReadLimit ? $timestamp : $this->historyReadLimit);
+      $history_read_limit = REQUEST_TIME - $this->historyMarkRead;
+      $timestamp = ($timestamp > $history_read_limit ? $timestamp : $history_read_limit);
 
       // Use the timestamp to retrieve the number of new comments.
       $query = $this->entityManager->getStorage('comment')->getQuery()
diff -u b/core/modules/forum/src/ForumManager.php b/core/modules/forum/src/ForumManager.php
--- b/core/modules/forum/src/ForumManager.php
+++ b/core/modules/forum/src/ForumManager.php
@@ -307,16 +307,19 @@
    *   previously viewed the node; otherwise - history read limit.
    */
   protected function lastVisit($nid, AccountInterface $account) {
+    $history_read_limit = $this->configFactory
+      ->get('history.settings')
+      ->get('history_mark_read');
     if (empty($this->history[$nid])) {
       $result = $this->connection->select('history', 'h')
         ->fields('h', ['nid', 'timestamp'])
         ->condition('uid', $account->id())
         ->execute();
       foreach ($result as $t) {
-        $this->history[$t->nid] = $t->timestamp > $this->history_read_limit ? $t->timestamp : $this->history_read_limit;
+        $this->history[$t->nid] = $t->timestamp > $history_read_limit ? $t->timestamp : $history_read_limit;
       }
     }
-    return isset($this->history[$nid]) ? $this->history[$nid] : $this->history_read_limit;
+    return isset($this->history[$nid]) ? $this->history[$nid] : $history_read_limit;
   }
 
   /**
@@ -474,6 +477,9 @@
    * {@inheritdoc}
    */
   public function unreadTopics($term, $uid) {
+    $history_read_limit = $this->configFactory
+      ->get('history.settings')
+      ->get('history_mark_read');
     $query = $this->connection->select('node_field_data', 'n');
     $query->join('forum', 'f', 'n.vid = f.vid AND f.tid = :tid', [':tid' => $term]);
     $query->leftJoin('history', 'h', 'n.nid = h.nid AND h.uid = :uid', [':uid' => $uid]);
diff -u b/core/modules/history/config/install/history.settings.yml b/core/modules/history/config/install/history.settings.yml
--- b/core/modules/history/config/install/history.settings.yml
+++ b/core/modules/history/config/install/history.settings.yml
@@ -5 +5 @@
-history_mark_read: '2592000'
+history_mark_read: 2592000
diff -u b/core/modules/history/src/Plugin/views/filter/HistoryUserTimestamp.php b/core/modules/history/src/Plugin/views/filter/HistoryUserTimestamp.php
--- b/core/modules/history/src/Plugin/views/filter/HistoryUserTimestamp.php
+++ b/core/modules/history/src/Plugin/views/filter/HistoryUserTimestamp.php
@@ -34,7 +34,7 @@
       $configuration,
       $plugin_id,
       $plugin_definition,
-      REQUEST_TIME - $container->get('config.factory')->get('history.settings')->config->get('history_mark_read')
+      REQUEST_TIME - $container->get('config.factory')->get('history.settings')->get('history_mark_read')
 
     );
   }