We have asterisks for emphasis , attachments for screenshots, and bulleted lists for a subset of tables. More complex tables and formatting probably work better

We have asterisks for emphasis , attachments for screenshots, and bulleted lists for a subset of tables. More complex tables and formatting probably work better in an attachment; the message body should be clear, concise, and render correctly in the recipient's mail client. When the body contains complex HTML, there's a good chance it'll render incorrectly in someone else's client. Allowing fewer features is a feature in itself: when we try to allow everything without thinking about the consequences, we end up with something like the modern Web or Electron apps.