Why did join and leave messages disappear from the game chat?

The game chat now shows only the conversation between players. Lines like “player joined”, “player left”, “removed by the organizer” and other system messages moved out of the chat into the Game Logs tab of the game analytics. To check who joined or left and when, open the Analytics row in the lobby, then the Game Logs tab and pick the Participants filter. This only changes where the history is shown, nothing is lost for new events. Messages written by people stay in the chat as before.