For example, May is planning a surprise party for Yang. She sends Cynthia the party details in Messenger using vanish mode so that the message will disappear. The message will no longer be visible to May once she leaves the chat, and Cynthia will see the message only the first time she opens the chat thread.

After Cynthia reads the message, the content is deleted after one hour. If Cynthia never reads it, it’s deleted after 14 days.