XR Plugin Manager - Plugin Provider Checkbox doesn't work

Hi!

The checkbox used to choose an XR plugin provider under each build target doesn't work in the Editor Project Settings.

Please See Attached Gif.

I've tried restarting the editor and completely re-installing all packages. Doesn't work.

When I build I get this error message in Xcode, so it seems to affect my ability to use the plugin:

"No active UnityEngine.XR.XRInputSubsystem is available. Please ensure that a valid loader configuration exists in the XR project settings."

Unity 2019.4.4f1
AR Foundation 2.1.8
AR Subsystems 2.1.2
ARKit XR PLugin 2.1.9
XR Interaction Subsystems 1.0.1
XR Plugin Mangement 3.2.13