What just happened? Messenger is the second-most-popular messaging app in the world, but not every user has a Facebook account. Now, however, that's no longer an option for new signups after the company removed the ability to use phone numbers instead of a FB account.

It was back in 2015 when the social network started allowing people to sign up for Messenger without a Facebook account. Phone numbers, photos, and names were all accepted as forms of login identification, but a change in the company's Help Center website states that "you'll need to create a Facebook account to use Messenger."

Facebook confirmed the new rule to VentureBeat. "We found that the vast majority of people who use Messenger already log in through Facebook and we want to simplify the process," said a company spokesperson.

The good news for those already using Messenger without a Facebook account is that the change won't affect them; it only applies to those "new to Messenger." But some Redditors claim otherwise, stating that the app is informing them their accounts are restricted. Whether this is due to a bug or something else is unclear.

The change is likely related to Facebook's plan to unify all of its messaging apps, which will allow users to send messages across WhatsApp, Instagram, and Messenger. The three apps boast almost 3 billion monthly active users combined, with WhatsApp being the most popular (1.5 billion MAUs).