MediaTrackSupportedConstraints: displaySurface 属性

async function capture() {
  let supportedConstraints = navigator.mediaDevices.getSupportedConstraints();
  let displayMediaOptions = {
    video: {},
    audio: false,
  };

  if (supportedConstraints.displaySurface) {
    displayMediaOptions.video.displaySurface = "monitor";
  }

  try {
    videoElem.srcObject =
      await navigator.mediaDevices.getDisplayMedia(displayMediaOptions);
  } catch (err) {
    /* handle the error */
  }
}