diff --git a/include/class.forms.php b/include/class.forms.php
index 4252be233d1a6ac056ed10992c3ed6f67888f766..02d59862cc8170d2e2b02ba6aa7219cd304965e7 100644
--- a/include/class.forms.php
+++ b/include/class.forms.php
@@ -3965,7 +3965,7 @@ class FileUploadWidget extends Widget {
           allowedfiletypes: <?php echo JsonDataEncoder::encode(
             $mimetypes); ?>,
           maxfiles: <?php echo $config['max'] ?: 20; ?>,
-          maxfilesize: <?php echo $maxfilesize; ?>,
+          maxfilesize: <?php echo str_replace(',', '.', $maxfilesize); ?>,
           name: '<?php echo $name; ?>[]',
           files: <?php echo JsonDataEncoder::encode($files); ?>
         });});