Bug? page header supresses title in web page

when I fill in a title …

and a page header …

then page header supresses title:

is this normal?

I think this is the default behavior. If header is not set and no h1 tag is in the body, header is set as title.

even if the field for title is filled in?
this is not intuitive at all
i try to understand … for what reason does it work this way?

If both title and header are given, one of them has to take priority over other, so header seems more appropriate.