The description at https://immersive-web.github.io/webxr/#xrrenderstate-interface currently says, "There are multiple values that developers can configure which affect how the session’s output is composited. These values are tracked by an XRRenderState object." Most [1] other sections describing a type begin with "An XRFoo represents..."

In addition, use of XRRenderStateInit and XRRenderState, including how and when the former is applied, is non-obvious, so it would be nice to provide more information on this. Some of that may belong in updateRenderState() (see #676), but it probably makes sense to document the overall design and use in one location.

[1] XR and XRSession are notable exceptions.