diff --git a/core/modules/rdf/rdf.module b/core/modules/rdf/rdf.module
index c2b75b7..e9140c6 100644
--- a/core/modules/rdf/rdf.module
+++ b/core/modules/rdf/rdf.module
@@ -443,8 +443,8 @@ function rdf_preprocess_comment(&$variables) {
     // Wraps the 'author' and 'submitted' variables which are both
     // available in comment.html.twig.
     $author_attributes = new Attribute(['rel' => $author_mapping['properties']]);
-    $variables['author'] = SafeMarkup::format('<span@author_attributes>@author</span>', ['@author_attributes' => $author_attributes,'@author' => $variables['author']]);
-    $variables['submitted'] = SafeMarkup::format('<span@author_attributes>@submitted</span>', ['@author_attributes' => $author_attributes,'@submitted' => $variables['submitted']]);
+    $variables['author'] = SafeMarkup::format('<span@author_attributes>@author</span>', ['@author_attributes' => $author_attributes, '@author' => $variables['author']]);
+    $variables['submitted'] = SafeMarkup::format('<span@author_attributes>@submitted</span>', ['@author_attributes' => $author_attributes, '@submitted' => $variables['submitted']]);
   }
   // Adds RDFa markup for the date of the comment.
   $created_mapping = $mapping->getPreparedFieldMapping('created');