Any info on new initial support for passthrough camera on Meta browser v38.2?

Is there any API info, documentation, or code samples regarding access to the passthrough camera api in WebXR as per the Meta Browser 38.2 Release notes?  I am assuming this is to allow access the the front facing cameras as a texture available to use in AI models or for other purposes using the passthrough camera api (not as a background like traditional AR, but allowing javascript access to the actual data from the camera stream, which would be new to Quest WebXR and very powerful!)