Conversations in Vanish Mode on Messenger and Instagram disappear after they are seen, and the chat window is closed.
Vanish Mode on Messenger has been rolled out in the US and a few countries, and will be launched on Instagram soon, followed by a gradual rollout on both platforms in more countries. Some users reported having access to this feature in India.
Users can swipe up in the chat window to enable vanish mode, and swipe-up again to disable it. When a user turns on Vanish Mode, it is turned on for everyone in the chat.
If anyone in the chat takes a screenshot of the conversation before it disappears, the user will be notified.
The update is a part of the new Messenger experience integrated with Instagram. The update merges messaging on both platforms in one experience, allowing users on the Messenger app to reach a friend on Instagram.
Additional features such as Selfie stickers, Watch Together, and more were also introduced with the update, along with bringing Messenger features such as replying to a specific message, forwarding a message, and customisable chat colours, to Instagram.
Facebook apps have recently been focussing on ephemerality, WhatsApp also recently introduced disappearing messages for a chat.