QToolButton not using programmatically set QIcon variations

if you create a QIcon programmatically, and add QImages to it for all the states, then programmatically set it into a QToolButton, then, when the user clicks the button, the button does not show the "pressed" variant, or when the window is disabled, the button does not show the "disabled" variant

on Windows, the button "depresses" down and to the right, instead of drawing the "pressed" variant. ??

see minimal project, attached