OpenGL RenderWindow in sandboxed iframe console error

[PaulHax]

High-level description

When using OpenGL RenderWindow in a iframe (without xr-spatial-tracking feature policy?) get this error on first render:

Uncaught (in promise) DOMException: Failed to execute 'isSessionSupported' on 'XRSystem': Access to the feature "xr" is disallowed by permissions policy.
    at vtkOpenGLRenderWindow (webpack-internal:///./node_modules/vtk.js/Sources/Rendering/OpenGL/RenderWindow/index.js:221:75)

Steps to reproduce

Use vtk.js in "sandboxed" iframe

<iframe
  id="inlineFrameExample"
  title="Inline Frame Example"
  width="300"
  height="200"
  src="./viewer.html"
  sandbox="allow-scripts"
>
</iframe>

https://codesandbox.io/s/volume-rendering-bounds-forked-846gd7?file=/index.html:119-304

Expected behavior

No XR related errors unless I opt into trying to activate XR.

Environment

• vtk.js: 25.4
• OS: Linux
• Browser: Chrome 103

Reported here:

Kitware/itk-vtk-viewer#534

Approach?

Looks like xr.isSessionSupported returns a Promise, so maybe something more like this:

if (navigator.xr) {
    navigator.xr
      .isSessionSupported('immersive-vr')
      .then(isSupported => {
        isImmersiveVrSupported = isSupported
      })
      .catch(error => {
        if (error.name !== 'SecurityError') {
          throw error
        }
      })
  }

Or remove this feature and lift this to user responsibility. I'm not seeing in repo use of HaveVRDisplay event.

[YaoDongcai]

In fact, you can handle it according to the following:

Object.defineProperty(navigator, "xr", {
get: function () {
return undefined;
},
});