Menu Options Not Fully Hidden

Maybe the selector is different. Is that an automatically option or added you an custom option? Also you can always add custom to hide this area.

It is the automatic option, but I also tried adding the custom option with the same result.

You mean the meta box? is also visible after to try with custom options. Have you the right selector?

I have tried social_warfare and social_warfare.postbox for the slug and put it under Write Options – Post

I am obviously missing something, see screenshot here https://www.screencast.com/t/wAf26hYj0pX