public final void showDrawer(Region drawer, Side side) {
        showDrawer(drawer, side, -1);
    }
Shows the {@code drawer} on the defined {@code side} in the {@link Workbench}.

@param drawer to be shown
@param side   of the workbench, on which the {@code drawer} should be positioned
@implNote Sizes the drawer according to the computed size of {@code drawer}.
However, it will take up a maximum of 90% of the screen, to allow the user to still
close the drawer by clicking on the {@link GlassPane}.
workbenchfx-core/src/main/java/com/dlsc/workbenchfx/Workbench.java