diff --git a/modules/monitoring/library/Monitoring/Web/Widget/CustomVarTable.php b/modules/monitoring/library/Monitoring/Web/Widget/CustomVarTable.php
index 4cbdad52c..b29c238ad 100644
--- a/modules/monitoring/library/Monitoring/Web/Widget/CustomVarTable.php
+++ b/modules/monitoring/library/Monitoring/Web/Widget/CustomVarTable.php
@@ -203,6 +203,7 @@ class CustomVarTable extends BaseHtmlElement
     {
         $table = new self($entries);
 
+        /** @var HtmlDocument $wrapper */
         $wrapper = $this->getWrapper();
         if ($wrapper === null) {
             $wrapper = new HtmlDocument();