Irrelevant if I add a Sticky Navigation Logo or not : The only thing that shrinks when I start scrolling is the Logo but not the navigation bar itself.
When I keep both settings above the same e.g. on 60 it all works fine but I like the effect that the sticky header shrinks a little upon scrolling and the documentation mentions that this should be possible.
(for completeness : On the home page only I have a header element to make the initial header transparant but I observe the same non-shrinking behavior on other pages where the header element is not active (e.g. the “blog” page).