How do I make a private chat room? [duplicate]

Question

In the access tab of a chat room's info page, the Explicit read access section says:

Even when this room is private, these users will be able to read the conversations in this room.

This implies that there are private rooms, but I can't find any option to make a room private.

1. I can't find the button.
2. The access group doesn't do anything.
3. One of those magical things that has to do with diamonds in one's name.
4. Other.

Answer 1

You can't.

Absolutely private messaging is for moderators only. They have their own private chat room, and can send users private messages.

Other users can only create completely public, and gallery rooms. The transcript is always public.