Yes, i forgot to mention Writer Mode which of course as you managed to discover yourself, take precedence and force-hide Title bar & Status bar (regardless of toggles)
You are right - description should more explicitly mention this - i will change it in next release so there is no confusion in the future.
Anyway, i am glad you have worked this out - in fact i am using the modes almost exactly as you described: with hotkey but minus Title bar as i don’t need it - i always write in fullscreen mode
Cheers from Poland, and thanks for using the theme. Don’t hesitate to shoot if you stumble upon some other issues