A new beta version of WhatsApp, v2.19.275, has integrated an interesting option: that of allowing users to send messages that destroy themselves after a certain time.
You have analyzed the code of this latest version has indicated that this option allows you to set times of 5 seconds and an hour to mark when these messages will self-destruct, which will disappear from the chat and thus allow users to have those ephemeral messages that for example were already present on Telegram.
This message will self-destruct in 5 seconds.
Telegram's secret chat option offers that ability to its users, and with it those who interact in a conversation can make the messages they write self-delete after some time.
Users, long ago could enjoy deleting messages they have sent unwanted, but the feature can not be programmed.
In the code discovered by WABetaInfo, three options for those messages that are self-destruct are shown for now: either we deactivate that option, or self-destruct in 5 seconds, or self-destruct in one hour.
The option seems to be available in group chats, so it is not known if it will also appear in private chats.
In fact, the option is deactivated and hidden in this beta version analyzed by this expert, which indicates that it is still in the development phase.
There is therefore no estimated date of appearance of this capacity, so we will have to be patient.