I have reviewed this document as part of the security directorate's ongoing effort to review all IETF documents being processed by the IESG. These comments were written primarily for the benefit of the security area directors. Document editors and WG chairs should treat these comments just like any other last call comments. This document registers the ‘text/markdown’ media type. Specifically excluding any potential security concerns regarding browsers rendering Markdown files in the future, there are no direct internet security implications associated with the registration of this media type. I consider this document ready for publication. -Shaun