Jean (Rookie) tends to free/take a long time
I have played several multiplayer games (basic and seafarers) with Jean (Rookie) in either slot 3 or slot 4 and had problems. The turn timer was disabled. Some times when it was Jean's turn she would take a very long time - more than 3 minutes. It looked like the game froze. Sometimes, if I refreshed my browser window and reconnected then Jean would continue on. Other times not. I have only had this happen with Jean (Rookie). I haven't tried other variations of Jean yet.
Jean, Vincent, whoever it doesn't matter. It happens all the time with AIs. Refreshing your browser is so far the only workaround