How to make Subject line display bigger?

I would like the subject line in the Message pane to display larger. I cannot figure out how to do this via the app Settings or Theme. It would also be great if I could make it larger and bold in the Preview pane as well (only the Subject, not the message preview lines). Help?

Nobody? My subject line is like 10pt when the rest of the eM Client app displays as 16pt or higher. This is ridiculous. Subject lines are important, and it’s barely legible on my 4K display.