Line highlighting and dark mode for inspector inactive

iMac High Sierra/Catalina, when I choose line highlight in preferences it doesn’t translate into the text. I work with HighSierra on my iMac and Catalina on my MacBook Pro, neither display the choice. And incidentally, the same ‘page’ in preferences - the option of dark mode for inspector is also not responding.

So why are you posting in the Scrivener for iOS forum?

Wow. I’m way too used to the polite and helpful attitude of people in the Apple help forum.
Are you seriously suggesting that I posted something for fun in the wrong place rather than in error? Happy if you suggest where I should post this, since you seem to know?
I have no idea what kind of answer you expect or how this helps me finding an answer to my question.

BTW, Figured out a part answer by trial and error. Still can’t figure how to highlight the line I’m writing in when writing outside of composition mode.