his web app will send you a confirmation email to make sure you own the email address. In that email there will be another link. Click that link and you will be taken to a page where you can trigger test emails to be sent to you. Those test emails are specially crafted to use a variety of techniques, to attempt to send information back to this server when read. It will then display the results for you.

The project is available at https://gitlab.com/grepular/ept3