Since the release of the Delete for Everyone feature, many users have complained about the limit of 8 minutes and 32 seconds to revoke a message, and that when the user deletes a message for everyone, for the recipient it’s possible to understand that a message has been revoked reading “This message has been deleted”.
To bypass the first problem, many users, thanks to modded and unauthorized WhatsApp for Android versions, were able to delete any message for everyone.. also messages sent 3 years ago!
Since the WhatsApp beta for Android 2.18.69 version, WhatsApp has extended the limit to delete messages for everyone to 2¹² seconds (4096 seconds, that is 8 minutes and 16 seconds), the same is applied to recent WhatsApp for iOS and Windows Phone updates.
But WhatsApp has also silently added something else to improve the Delete for Everyone feature in a few precendent updates.
In order to stop these bad users, WhatsApp has implemented a “Block revoke request” feature.
When the user deletes a message for everyone, WhatsApp sends to the recipient(s) a new message having the same ID of the message that the user wants to revoke.
Previously, when the recipient received this particular message contained the revoke request, the app checked if the ID of the message was present in the database: if the original message was found, WhatsApp directly deleted it without checking any other important information.
This algorithm has been recently improved: if WhatsApp finds a message in the database having the same ID of the received revoke message request, it checks the data of the message saved in the database, performing an operation: if [current date] – [the date of the saved message] is less than 24 hours, WhatsApp can successfully delete the message.
Adding this new operation, the recipient is sure that nobody can illegally delete messages for everyone.
WhatsApp has decided to choose 24 hours as time reference because an user can delete a message for everyone and the recipient’s phone might be turned off at that moment.
Choosing 24 hours, WhatsApp is sure that the recipient will surely receive the revoke request (seen that hardly an user doesn’t turn on his device within 24 hours), but this also means that:
• If the recipient won’t turn on his phone within 24 hours, the revoke request will be considered invalid, also if the message was correctly deleted for everyone within 1 hours 8 minutes and 16 seconds but, as above mentioned, this is an unusual situation.
• All users that are currently using modified and unauthorized WhatsApp versions can successfully continue to delete messages for everyone within 24 hours.
Note that we don’t recommend to install these modified WhatsApp versions.
It is a victory for all WhatsApp users that are respecting the rules.
Source by wabetainfo…