In xr.js you can see them checking for a status code >= 200 and < 300 so the documentation is wrong, it rejects if not 2XX. EDIT: Apparently this was changed r

In xr.js you can see them checking for a status code >= 200 and < 300 so the documentation is wrong, it rejects if not 2XX. EDIT: Apparently this was changed recently and was actually broken at time of posting.