It was already taking Facebook to add the bar with the most important tabs at the bottom for easier handling and thus accessing those most used sections.
The fact that every time mobiles are more elongated And that many of us have become accustomed to handling them with one hand, means that even the custom layers have been adapted to place the most important elements at the bottom of the screen. Facebook has already done it.
Facebook is an app that takes time to adapt to new trends, and although we have recently had another interesting 'bluish' change In the mobile menu, you have finally chosen to bring those tabs to the bottom of the application.
So it has passed those tabs located at the top to the bottom of the interface so that you can access them with one hand and with the greatest comfort in the world. A Facebook app to which one had been very reluctant because of how "heavy" it has always been, but which, due to the latest changes carried out, and a better experience, has been able to change one's mind.
All the six moved tabs are present in version 264.0.0.44.111 and although there is nothing more than this novelty, it does give another experience that we have been used to with Facebook. Some apps that continue to adapt to the times that play as has happened to Google Maps by moving its two labels from "to home" and "to pick up" for the coronavirus.
Facebook has released this new update regionally, so it is very possible that you still do not see the changes made. As with these slightly more "aggressive" changes to the interface, they usually spend days while receiving user feedback.