diff --git a/core/lib/Drupal/Component/Utility/Html.php b/core/lib/Drupal/Component/Utility/Html.php
index 9e8e813..76e0541 100644
--- a/core/lib/Drupal/Component/Utility/Html.php
+++ b/core/lib/Drupal/Component/Utility/Html.php
@@ -90,7 +90,8 @@ public static function cleanCssIdentifier($identifier, array $filter = array(
       $identifier = str_replace('__', '##', $identifier, $double_underscore_replacements);
     }
     $identifier = str_replace(array_keys($filter), array_values($filter), $identifier);
-    // Replace temporary placeholder '##' with '__' only if the original $identifier contained '__'.
+    // Replace temporary placeholder '##' with '__' only if the original
+    // $identifier contained '__'.
     if ($double_underscore_replacements > 0) {
       $identifier = str_replace('##', '__', $identifier);
     }