In fullscreen mode, there is no way to configure the following (from the
original bug#4363):
Using --without-toolkit-scroll-bars with the scrollbar on the left, the
window should be shifted a couple of pixels to the left. This helps to
avoid the unclickable and irritating no man's land between the left
screen border and the clickable scrollbar. Otherwise using the
scrollbar is more difficult as mouse movements must be very precise
horizontally - vertical precision would suffice. What I do here is
either to use a negative geometry to avoid that space or I manually
reposition that window.
Note that I am happy to find some clean (.emacs.el) way to do this.