WhatsApp-Facebook is testing WhatsApp a new feature called “lost messages” that allows you to send lost messages after long periods of time.
This phenomenon was observed by WABetaInfo In version 2.19.275 of WhatsApp for Android beta of the group chat group application. You can send a message that disappears from the conversation after five seconds or an hour.
WABetaInfo it states that this secret feature is being developed, and it is not known if it will be passed on to global users on a permanent platform. However, beta users are the first to leave, so if you are excited about this feature, you can sign up for the beta project and wait for it to arrive.