After a few weeks of beta testing Windows 10 Mobile users can now download a version of the official Facebook app that's been made specifically for that operating system. Windows Phone 8.1 users can also get an update for the Facebook app as well.
For Windows 10 Mobile phones, the version number is 10.1, while Windows Phone 8.1 users still have the old version number of 126.96.36.199. There are no new published change logs with this updated app so if you notice anything major, please let us know in the comments and we will update this post.
For those on the Facebook Beta for Windows 10 Mobile, technically this official version is newer. However, the beta is likely to continue to get updates and features ahead of the public version. As such, it is your choice if you want stable and public or a more cutting-edge experience with the beta program (you can also just install and use both).
Thanks to Jeffrey for the tip!