The restore property when initializing PubNub enables the subscribed client to reconnect with the last messages timetoken, for example, when navigating across different pages of a website. That setting is useful in the event that the client abruptly exits and is then restarted.

For example, the user closes the browser, then restarts the browser and resubscribes. In that scenario, the client would connect with the timetoken it last used and will continue from there to receive messages, possibly via a catch up of messages published during the disconnect period.