Scrolling with the scroll bar

[Eli Zaretskii]

The tutorial says:

  >> Try pressing the middle button at the top of the highlighted area
     within the scroll bar.  This should scroll the text to a position
     determined by how high or low you click.

  >> Try moving the mouse up and down, while holding the middle button
     pressed down.  You'll see that the text scrolls up and down as
     you move the mouse.

This is correct for the X build without any toolkits, but what about
the toolkit builds supported by Emacs?  At least on MS-Windows, you
need to click and drag mouse-1, not the middle button.  Aren't there
other toolkits where the middle button doesn't produce the described
effect, and mouse-1 should be used instead?