Enable option to disable chat in Webinar

Enable option to disable chat in Webinar with Webcast mode during the middle of the session

One of the customers had a Webinar with Webcast and the attendees who were streaming the Webinar were able to chat. Host attempted to disable the Chat by going to Participants->Assign Privileges->All Attendees->Communicate and disable chat. However this did not disable the chat for the Webcast attendees. If the host has missed disabling the chat during scheduling, they should be able to disable the chat during the session for all the Webcast attendees