Gator used to do that too!! He would lunge at the window and put his feet up on it and be going BALLISTIC!! He was actually quite scary in full protection mode

he even put on his big, deep, scary, aggressive bark. But once they were inside, he was fine and wanted to be besties and he loved everyone on walks, especially kids. Had no problems with strangers but was very protective and territorial. I have no doubt he would have given his life to protect any one of us.
I should also note we have a big bay window in the porch room and the house is higher than the garden so when you’re walking up, he looked even bigger than he was! Especially since he would stand in it. And he was like ~140 lb Black Lab/Great Pyrenees mix so already plenty big enough and tall enough without the added height of the window!

He scared quite a few delivery people