Explination

in this comic, the company is redhat air. they fly small airplanes, so they need to know the weight of their customers. but one of the people says that there's an "elephant in the room". what they mean is that there is litterally an elephant in the room of all their customers, thus, one of their customers is an elephant, which means it is too heavy to fly. the elephant in the room is that there's and elephant in the room.