> Real-time chat is the most obvious case where the html purist won’t offer an acceptable experience.

???

  <pre>If you have any questions:

  Phone:    <b>0123456789</b>  <a href="tel:+18123456789">[call me]</a>
  whatsapp: <b>0123456789</b>  <a href="https://wa.me/0123456789?text=I'm%20interested">[message me]</a>
  facebook: <b>html.purist</b> <a href="https://www.facebook.com/messages/t/html.purist/">[message me]</a>
  </pre>

https://jsfiddle.net/r3u5yvk8/

I'm now on their contact list.