HTML5 video screenshot

screenshot.js

canvas = document.createElement('canvas');
video = document.querySelector('video');
canvas.width = video.videoWidth;
canvas.height = video.videoHeight;
canvas.getContext('2d').drawImage(video, 0, 0, canvas.width, canvas.height);

canvas.toBlob((blob) => {
    dataURL = URL.createObjectURL(blob);
    const link = document.createElement('a');
    link.href = dataURL;
    link.download = 'screenshot.png';
    link.style.display = 'none';
    document.body.appendChild(link);
    link.click();
    document.body.removeChild(link);
    URL.revokeObjectURL(dataURL);
});