Just a heads up, ever since Unity 5.6, Unity broke FB standalone integration (100% Unity -- not FB -- all versions of FB SDK work fine in 5.5 and works in 5.6 editor, just not when compiled -- Unity thinks FB standalone is Gameroom, so if you don't have Gameroom as target build, it will say you're missing Gameroom and not ever init).
If you use FB in any form other than the Gameroom target build (FB's answer to Steam), it will work in the editor, but NOT when compiled. This means if you use it for Android, iOS, Windows, Linux, Mac, etc -- it won't work.
This, to my knowledge, was never fixed (let us know if you are testing a version that works with it, but we had to abandon FB long ago).
Just a heads up for those using or plan to use FB integration.