pp extends WebXRSampleApp {
        getXRTarget() {
          for(let radio of xrTargets) { 
              if(radio.checked) return radio.value; 
          } 
        }
        
        onCreateGL() {
          const gl = createWebGLContext({
            webgl2: true,
            antialias: false, // Antialiasing will be handled manually.
            xrCompatible: true
          });
          document.body.appendChild(gl.canvas);

          this.multisampleFramebuffer = gl.createFramebuffer();

          th