GUI Minimize/Maximize inGame Resolution Glitch

A glitch that when loading or generating a New World and you press Minimize before it starts loading or generating;
when it starts loading or generating a new World and you press the Maximize button ** while loading or Generating ** , the window goes full screen but the game remains unchanged.

Obviously the image below was edited but i made it look as much like the real scenario as i could in Paint. the Minecraft Screenshot is real. This is not fake.