VRDisplayCapabilities

function reportDisplays() {
  navigator.getVRDisplays().then((displays) => {
    displays.forEach((display, i) => {
      const cap = display.capabilities;
      // cap is a VRDisplayCapabilities object
      const listItem = document.createElement("li");
      listItem.innerHTML =
        `<strong>Display ${i + 1}</strong><br>` +
        `VR Display ID: ${display.displayId}<br>` +
        `VR Display Name: ${display.displayName}<br>` +
        `Display can present content: ${cap.canPresent}<br>` +
        `Display is separate from the computer's main display: ${cap.hasExternalDisplay}<br>` +
        `Display can return position info: ${cap.hasPosition}<br>` +
        `Display can return orientation info: ${cap.hasOrientation}<br>` +
        `Display max layers: ${cap.maxLayers}`;
      list.appendChild(listItem);
    });
  });
}