An online social networking system receives user interactions with a content item from client devices of users of the social networking system. A public user interface displaying at least some of the received user interactions with the content item is provided for display on each of the client devices. A request to initiate a private session associated with the content item is received from a client device of a first user. The request identifies a subset of the users including the first user. User interactions with the content item from client devices of the subset of the users are received within the private session. A private user interface for interacting with the content item is provided for display on each of the client devices of the subset of the users. The private user interface displays the user interactions received within the private session.