https://i.gyazo.com/24bd17971d285c6f21744bdb5f1a9479.mp4
If you don’t focus and then unfocus each client then the gamepad will control them regardless of focus. I remember this being a bug back when gamepad support was added. I guess it never got fixed.
I remember reporting it last time and I can confirm that it did get fixed shortly after and the latest studio build re-introduced the bug.
It’s still happening!
I plugged my controller in before and after I started a Test Server as well as trying in a new place. I can still controll all the players in my test server.