control key
When I hit the Control key, any open windows disappear. They basically are shoved off the sides of the screen so the home screen is displayed. I can't use the Control key for anything else. I have tried to find something in the keyboard shortcuts that would tell me that it's on so I can turn it off, but I have found nothing.
I just upgraded to Ventura on my Macbook. I was hoping that would cure the problem, but it didn't.
MacBook Pro 15″, OS X 10.11