As the title suggests, I think there's a strafing bug with this camera. Using the left/right arrow keys to strafe also causes the camera to rotate. Forward motion also behaves strangely. This makes for very confusing controls when simultaneously moving the mouse to pivot the camera. I've tried this in both the stable and latest versions.
https://playground.babylonjs.com/indexStable.html#U2754M#1
I also provided a Universal camera to show the difference in behaviors.