diff --git a/core/lib/Drupal/Component/Utility/Tags.php b/core/lib/Drupal/Component/Utility/Tags.php
index 628ce70..6caa848 100644
--- a/core/lib/Drupal/Component/Utility/Tags.php
+++ b/core/lib/Drupal/Component/Utility/Tags.php
@@ -74,7 +74,7 @@ public static function implode($tags) {
     foreach ($tags as $tag) {
       $encoded_tags[] = self::encode($tag);
     }
-    return implode(', ', $encoded_tags);
+    return implode(',', $encoded_tags);
   }
 
 }