State of Visual Editor fonts

Hi,

I've looked at the documentation and Googled a lot, but I couldn't find a way to change the main font used by the Visual Editor (I'm referring to non-code block text).

Is this possible at all?

Not with built-in tools. You could change the font by taking advantage of the fact that RStudio's theme files (.rstheme) are just CSS files, so you could make your own theme (or modify an existing one) to add CSS rules that force the Visual Editor's main font to the one you want.

If you right click -> Inspect Element in the Visual Editor, you can see how it's getting its font; specifically the class you'd want to override is pm-proportional-font.