Mailto links are used to redirect to an email address instead of a web page URL. When a user clicks on the Mailto link, the default email client on the visitor's computer opens and suggests sending a message to the email address mentioned in the Mailto link.
If a website contains "mailto" links, it is possible to scrape email addresses from it regardless of the website structure.
A standard "mailto" link looks like this in the HTML source code:
<a href="mailto:email@example.com">Send Email</a>
<a href="mailto:email@example.com, secondemail@example.com">Send Email</a>
So the XPath below may work wonders in some cases:
//a[contains(@href,'mailto')]
As for where to input this XPath, you may refer to this tutorial: Customize element XPath