I think I raised this point before, but can't find the original location. I still think we should consider showing the HTML editor on the right instead. On a field that has a lot of content (eg, is larger than the entire editing area), clicking on HTML editor button does nothing except change the icon, as the HTML editor is hidden/shown outside of the visible area. Even if it does fit on the screen, the user may have to scroll up and down to see how changes made to one of the editors affect changes in the other editor, reducing the usefulness of showing them both on the screen at once.