Blank HTML emails at outlook.com

Just came across this odd behaviour  – using sendEmail() on a cfWheels app to send registration emails to a hotmail or outlook.com address results in a blank page.

The email and it’s source get through fine, including plaintext variants, but just don’t display.

The culprit? any tags (i.e, <foo>) within a CSS comment. How absurd is that? Well, hopefully it helps someone, somewhere.