UPDATE (11/7): A few more details have emerged about the upcoming Facebook Messenger unsend feature we first heard about last month.

In its notes for Messenger for iOS version 191.0, released Tuesday, Facebook said the unsend feature is "coming soon." Now, for the lame part: the feature will only let you retract a message within 10 minutes of pressing send.

"If you accidentally send the wrong photo, incorrect information, or message the wrong thread, you can easily correct it by removing the message within 10 minutes of sending it," Facebook wrote.

That's a pretty narrow window, which doesn't give you much time to mull it over. If, for instance, you wake up in the morning regretting some desperate messages you sent your ex after too many glasses of wine the night before, you'll be out of luck.

Facebook-owned WhatsApp gives you more than an hour to delete messages after sending them and rival messaging app Telegram gives users 48 hours to unsend messages.

Original Story (10/12):
Facebook may be getting closer to launching an unsend feature for Facebook Messenger.

On Friday, the developer Jane Manchun Wong posted screenshots of the "Unsend Message" button, which she spotted running as a test function in the app's code.

The feature appears to be pretty straightforward, but according to Wong, you'll only be able to unsend a message within a certain time limit. "After that time limit, the message will no longer be unsendable," she tweeted.

On Friday, Facebook declined to say when the feature will actually arrive, but it remains in the works, a company spokeswoman said.

Currently, you can't retract what you send over Facebook Messenger; you can only delete the message from appearing in your chat, not from the other person's inbox. However, Facebook has been willing to bend the rules when it comes to the company's own executives, including CEO Mark Zuckerberg.

According to Techcrunch, the company decided to retract messages Zuckerberg had sent to several users over Facebook Messenger, but without their consent. The social network said this was done for corporate security purposes and pointed to the 2014 hack on Sony Pictures, which led to the leaking of private email messages from several top executives. Nevertheless, the whole episode raised questions over why normal users on Messenger don't possess the same privileges.

Facebook responded by saying in April that an unsend feature was going to arrive for all users. However, it's been six months later and the ability to undo your messages still isn't here. Meanwhile, Facebook's other property, Instagram, does let you unsend direct messages. In June, Snapchat decided to add a message recall feature too.

The closest thing Messenger has to an undo feature is through the "Secret Conversations" feature, which lets you set a timer on how long you want a message to remain visible to the other user. You can learn more about this feature and other tricks for Messenger here.