https://agenciapara.com.br/email_tracking_links.asp?c=20417-11e6fc96ab4947513b60214735e999e0-4228887

This is display.cgi (source). It takes some text you enter into a form, and displays it for you as HTML. This is a great way to see how some HTML code looks in your (or someone else's) browser. So paste 'n go: