Maybe I don't understand what the htmlText attribute actually does. What I had hoped was that it would let me set the initial markup for the text edited in the control.
The default is to wrap html and body markup around everything. I just wanted to have everything as is, or else with just a div around it. However, whether the fxml has the default htmlText or a empty string for the htmlText, the string returned from the control itself is always wrapped in html and body tags. So if I want to pull out the text that was entered, then I need to parse it out of what is returned by the control. Not optimal, but workable.