Joomla! Documentation™

To create a mail template override within a custom template:

1. Go to System -> Site Templates -> Open your template (e.g., Cassiopeia).
2. In the Create Overrides tab, select joomla -> mail.
3. Joomla will copy the `mailtemplate.php` file to your template's `/html/layouts/joomla/mail/` directory, where you can modify it as needed.