Here is a tip: scrolling is MUCH easier if you use the scroll wheel on your mouse, instead of clicking and dragging the scroll bar buttons.
Just try it: put your mouse anywhere on the scroll bar,for example the small horizontal one at the bottom right. You don’t have to aim for the scroll bar button, put it anywhere on the bar. You don’t have to be precise either, because the bar area is bigger than the thin line itself.
Now move the scroll wheel on your mouse and you will (hopefully) agree that this is not so bad after all.