UPDATE (April 21): After being cancelled because the stickers peeled off, the STM has restarted the project.
The STM has begun a pilot project in an effort to reduce boarding problems at metro stations, particularly during rush hour. The idea is to mark where the doors open (they always open at the same place), and create a buffer zone so that people can exit the train safely while others wait off to the side to get on. Believe it or not, this is actually a problem: people are so desperate to get on that they crowd the doors and don’t leave any room for people to get off. Sometimes it can be like trying to get to the stage of a rock concert.
The project is in place at three platforms, each with a different design.