Hmmm, that is ultra weird. I’m going to say it must be definitely a bug. Can you try it on a totally new file with the default cube? Just to see if it’s that file you have or if it’s the Blender version you have in general. I guess a couple of things I would do is to update stuffs on the computer, Windows update, Video Card drivers updates, then re-download Blender and try it out again.