I tried changing the size of the smaller window, and it worked briefly to allow the ball to bounce off the now-larger size, before the game snapped the window s

I tried changing the size of the smaller window, and it worked briefly to allow the ball to bounce off the now-larger size, before the game snapped the window size back to the original. It made me think that changing the window could be part of the game somehow. Perhaps as you drag it bigger the playing field of the smaller game increases in width, so that game becomes harder (and also you can't move the paddle as far because your new window is too big to drag). Or maybe you should be able to capture the ball in the big window into the smaller window, and the size and position of the smaller window determines its entry point.