Scroll down line at the right side of the screen

Is there a purpose that when I stand in the BLOKS (or other) then the scroll line at the right side of the picture also scrolls down when it supposed to stand still ?

Sorry I didn't quite understand; did you mean that in the blocks tab that there are two scroll bars?
That's just a feature; the outer scroll bar allows you to scroll down to view uploaded media (if any), while the inner one hels you view your blocks.