On the session screen, the participant avatars sometimes fade, turn orange or red, why is this?

When a participant leaves the DisplayNote app, either by opening another app returning to the device home screen, the participant’s avatar will show this change in status by turning orange. A further 30 seconds without reconnecting will turn the avatar red to indicate a participant hasn’t returned to the session. Lastly, a faded avatar is someone who has disconnected from the session altogether.