The current pre-release of the client ("pioneer" in the version) is only compatible to itself. So you can only play with other testers. Please be aware!
Things that were mods get forced into your game and enabled by default, but probably missing functionality you wanted, then you get a patch that lets you turn them off, then they get removed and go back to being mods again. It's the new nightmarish cycle of trying to use your UI in FAF.
