When the Asgard monsters are unleashed and Captain America hits the wolf with his shield, a large ogre behind him tossing Hydra soldiers around suddenly disappears. Later, the creature is seen fighting Bucky and being knocked against a transformer, which explodes, obliterating the monster. Still later, the monster is seen again fleeing back through the portal.
World War II era newsreel footage shows an American flag with 50 stars. At the time the flag had only 48 stars.