If you have been putting off migrating to Facebook’s Messenger app on your mobile device, you won’t be able to put it off much longer. Facebook is already cutting off access to messaging section on the main app. You are in the minority if you are still able to see the “Never mind” button on your app. Once you get completely cut off though, you will be able to see that you have messages but you will only be able to view them once you are in Messenger app or using the Web version of Facebook.
Source: Gizmodo