>In summary: in order to display HTML emails using Mutt, the author developed a system to automatically pipe them to a tool that parses plaintext multipart MIME

>In summary: in order to display HTML emails using Mutt, the author developed a system to automatically pipe them to a tool that parses plaintext multipart MIME messages and converts them to an HTML file, which gets displayed in an auto-reloading Firefox tab. The article has nothing to do with reading HTML emails using mutt which is actually quite easy to do, as pointed out by another commenter. The article is about sending multi-part text+HTML emails in a nice way that handles attachments, inline images, etc.