Markdown in an entries Notes field (not a Secure note) oddity?

Thanks, 1P_Tommy, but that’s not quite what I as talking about. I understand well that yyy* results in bold, which is what I would expect in markdown. It’s the larger font bolded “xxx” that I don’t understand. What seems to cause that is just putting a number of hyphen characters on the line following some text that results in that behavior. THAT’s what strikes me as odd!