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1. Start a discussion as described in Getting Started. In case you want to change permissions for an existing discussion, skip this step.
2. Click the lock icon in the discussion cloud. You will see a list of users who can view this discussion (empty for a new discussion if not specified otherwise for the space, see below for details).
3. Type names of a users and/or user groups to enable viewing this discussion for them. 
4. Talk

   id	talk-180

   To delete a user/user group from a list, click  next to their name.
5. Click Apply to save changes.

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