If you want to see it you can quickly get it (at least with the latest Mac OS, I don't know about Windows). Having a thing across the top is perpendicular and

If you want to see it you can quickly get it (at least with the latest Mac OS, I don't know about Windows). Having a thing across the top is perpendicular and doesn't relate to the vertical structure of a scrolling page. You have change the vertical position of your eyes to see it in a context where vertical position is significant.