Cannot change highlight color in markdown doc

I am working with the current DT4 beta. When writing in Markdown, I cannot change the highlight color from the present garish dayglo yellow. I try to change color using the pulldown menu, but clicking on a different color in the pulldown changes nothing in the doc. Any suggestions or solutions welcomed. Thank you.

D

Welcome @dkeiger1
You cannot apply different highlight colors in Markdown beyond adding a custom CSS style for items with the mark tag.