A server system having one or more processors and memory storing one or more programs for execution by the one or more processors receives from a client device a request, the request comprising a request for message content from one or more email messages in a conversation thread. The server system responds to the request by identifying the message content, identifying candidate authors, and obtaining qualifying posts by the candidate authors, the qualifying posts satisfying predefined criteria. The server system furthermore selects a subset of the qualifying posts, and prepares the selected subset of the qualifying posts and the message content for concurrent display at the client device.