By default, CometService is active for chatrooms as well.
You can manually activate COMET_CHATROOMS (set it to 1) if you have subscribed to CometService or any third-party transport in cometchat/config.php file.
When using CometService with chatrooms, credits are deducted for every message received and NOT sent. So if there are 20 users in a chatroom and one message is sent, then 20 credits will be used.
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