main.js

let jspdf = document.createElement("script");
 
jspdf.onload = function () {
 
    let pdf = new jsPDF();
    let elements = document.getElementsByTagName("img");
    for (let i in elements) {
        let img = elements[i];
        console.log("add img ", img);
        if (!/^blob:/.test(img.src)) {
            console.log("invalid src");
            continue;
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        let can = document.createElement('canvas');
        let con = can.getContext("2d");
        can.width = img.width;
        can.height = img.height;
        con.drawImage(img, 0, 0);
        let imgData = can.toDataURL("image/jpeg", 1.0);
        pdf.addImage(imgData, 'JPEG', 0, 0);
        pdf.addPage();
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    pdf.save("download.pdf");
};
 
jspdf.src = 'https://cdnjs.cloudflare.com/ajax/libs/jspdf/1.5.3/jspdf.debug.js';
document.body.appendChild(jspdf);