diff --git a/helper.php b/helper.php
index c3d2182..521e9ec 100644
--- a/helper.php
+++ b/helper.php
@@ -74,7 +74,7 @@ function _getAvatarURL($user, &$title, &$size) {
     }
     
     if (empty($src)) {
-      $seed = md5(strtolower($mail));
+      $seed = md5(dokuwiki\Utf8\PhpString::strtolower($mail));
       
       if (function_exists('imagecreatetruecolor')) {
         // we take the monster ID as default
diff --git a/plugin.info.txt b/plugin.info.txt
index bfcdd93..cbeb39f 100644
--- a/plugin.info.txt
+++ b/plugin.info.txt
@@ -2,7 +2,7 @@
 base   avatar
 author Daniel Rodrigues, Michael Hamann, Gina Häußge, et al.
 email  danieldiasr@gmail.com
-date   2023-08-18
+date   2023-12-04
 name   Avatar
 desc   Displays avatar images
 url    https://www.dokuwiki.org/plugin:avatar