I had one of our German Shepherds go through our door some years ago.Fortunately,the UPS driver saw her coming and got the truck door shut just in time.
I don’t think they have any idea how strong they really are. When our GSD was still a puppy, he knocked an entire closet door off the hinges. His big, ole head just went sort of through it and he shook it off like it was a snow flake. They are big babies as well. He cried until I gave him a leather chew.