Montreal airport was a madhouse. I was on AC YUL-FRA and we were almost ready to leave then had to wait more than an hour for three passengers, already check in but stuck in security line. Of course, their baggage was by then in the hold. So if AC wanted to close the doors and leave them, the baggage had to be found and removed first. So we finally left 75 minutes late and many, including me, missed connecting flights out of FRA as a result.