diff --git a/src/OutputFilter.php b/src/OutputFilter.php
index ed8f5bb1..f95cf415 100644
--- a/src/OutputFilter.php
+++ b/src/OutputFilter.php
@@ -185,7 +185,7 @@ public static function stringUrlUnicodeSlug($string)
         $str = str_replace('-', ' ', $str);
 
         // Replace forbidden characters by whitespaces
-        $str = preg_replace('#[:\#\*"@+=;!><&\.%()\]\/\'\\\\|\[]#', "\x20", $str);
+        $str = preg_replace('#[:\#\*"@+=,;!><&\.%()\]\/\'\\\\|\[]#', "\x20", $str);
 
         // Delete all '?'
         $str = str_replace('?', '', $str);