This bad behavior of the FB messenger app does not surprise me.
Up/top of the picture is stored in the EXIF data in the image. Facebook purposely removes the EXIF data so that it is easier to steal the image. I would expect the same bad behavior from their messenger app.
Without the EXIF data the image viewers don't know which side is the top, so they display the image as physically stored. This tends to mess up images taken in portrait mode instead of landscape mode.