https://thenextweb.com/apps/2019/04/12/facebook-may-soon-let-you-chat-with-friends-on-mobile-without-messenger/

Five years ago, Facebook began encouraging users to use its standalone Messenger app to chat with their contacts, instead of using the built-in feature in the social network’s mobile apps. It appears that it’s now looking to bring messaging back to the primary Facebook app experience – which indicates a change in strategy for keeping users engaged on the platform

App researcher Jane Manchun Wong tweeted a screenshot of a Facebook feature in the works, which shows a new tab for messaging people right within the social network’s app. Currently, the chat button – on the Facebook app and mobile website – acts as a shortcut to the Messenger app. If you don’t have Messenger on your device, the shortcut will guide you to the App Store or Play Store to install it.