It may not be completely clear exactly what is happening in this video, but I had to take a shot of it. It showed the gentleman in the brown jacket pushing out the window to exit the carriage.

There was no commentary or description in either English or French, but I have a sneaking suspicion that this was intended to provide an explanation of how to exit the carriage in an emergency.

Either that, or we were going to be in for a very interesting time disembarking from the train when we reached Paris.