While most of the messenger has the ability to undo sent messages, Messenger is yet to have this feature. Now you cannot undo sent messages on Messenger, however, the Facebook-owned WhatsApp has this feature. This is a useful tool when you want to delete a message that was sent to a wrong person or sent a message with wrong content. Initially, Telegram had this feature but later, other social media communication companies started to implement this feature. WhatsApp allows you to delete messages that was sent by you from everyone, including the recipient. Initally, WhatsApp provided a time window of 7 minutes after which the message could only be deleted from the sender's device. If it was deleted within this time window, the message gets deleted from the recipient's device too. While some of the countries use Messenger most widely than WhatsApp due to availability of various third-party apps support, Facebook is testing the feature to undo sent messages on Messenger too.
Undo Sent Messages
Messenger is teseting out a "Delete Message for Everyone" feature on Messenger and it is called as "Unsend". There is no leak regarding the time limit within which the messages can be deleted for everyone. 
Few years ago, there was a controversial talk about few users complaining that messages received from Mark Zuckerberg got disappeared from the user's inbox. While the users were skeptical about it, Facebook said that they are testing out a feature like delete message for everyone on Messenger which unsends the message. Now Facebook has a live feature which is being tested out and should be rolled out to everyone after a few months. Messenger already had a secret conversation where the messages get deleted upon a time limit that a sender sets. That was a great feature which was used while sending photos to unknown people. However, at most of the times, we may forget whether a secret conversation is available or not as secret conversation on Messenger is not in a quick reachability, user experience wise. Are you excited for undo sent messages feature on Messenger? Let us know your thoughts in the comments below.