'content_changed'event. It is invoked when the document content has been updated due to changes made by any user in the session.
datawill contain a
'local'indicates local user changes, and
'remote'indicates remote user changes.
'users_update'event. It is invoked every time a new user joins a session or an existing user leaves a session
dataobject is an array that contains the current snapshot of users currently connected to the session. See
'users_update'event for details.