In my day-to-day, I often have to write rich text, that may include math formulae, and code snippets. For that, I use Markdown Here Revival. Unfortunately, when this is the case, MHR will "kill" the format of my smart templates, and the message will go out with nicely formatted formulas and beautified code, but with standard type and white background. It would be fantastic if both extensions could be made to work together!
I understand that this may be something to request to the MHR developers instead; I have not looked into the workings of either of the two. It is when MHR formats the text, right before sending, that the SmartTemplates formatting is lost.