Save HTML5 canvas element as PNG file

download-canvas.js

const canvas = document.getElementsByTagName('canvas')[0];
const dataURL = canvas.toDataURL('image/png');
const timestamp = Math.floor(Date.now() / 1000).toString(36).slice(2);
const link = document.createElement('a');
link.download = `download-${timestamp}.png`;
link.href = dataURL;
link.click();