Dear users, Our main database server crashed this morning around 9h15 UTC. The server was back online within 30 minutes. We are investigating the root of the issue, and we would like to apologize for the inconvenience. Best regards, Antoine Brenner PS: Should you have answered your lesson during the downtime we expect to have kept your answers even if our confirmation page did not state so (or simply did not show up). You should not need to re-do your lesson.