MediaDevices.getDisplayMediaやImageCaptureを利用してスクリーンショットを撮るデモ、たぶんChromeぐらいでしか動かない

capture-screenshot-demo.js

  const mediaStream = await navigator.mediaDevices.getDisplayMedia({
    preferCurrentTab: true,
  });
  const track = mediaStream.getVideoTracks()[0];
  const imageCapture = new ImageCapture(track);
  const imageBitmap = await imageCapture.grabFrame();
  const settings = track.getSettings();
  track.stop();
  const canvas = document.createElement("canvas");
  const ctx = canvas.getContext("bitmaprenderer");
  ctx.transferFromImageBitmap(imageBitmap);
  const blob = await new Promise((resolve) => {
    canvas.toBlob(resolve);
  });
  const objectUrl = URL.createObjectURL(blob);
  console.log({
    src: objectUrl,
    width: settings.width,
    height: settings.height,
    aspectRatio: settings.aspectRatio,
  });