How to save a webpage as PDF file using Puppeteer.js

const puppeteer = require('puppeteer');

class Webpage {
    static async generatePDF(url) {
        const browser = await puppeteer.launch({ headless: true }); // Puppeteer can only generate pdf in headless mode.
        const page = await browser.newPage();
        await page.goto(url, { waitUntil: 'networkidle', networkIdleTimeout: 5000 }); // Adjust network idle as required. 
        const pdfConfig = {
            path: 'url.pdf', // Saves pdf to disk. 
            format: 'A4',
            printBackground: true,
            margin: { // Word's default A4 margins
                top: '2.54cm',
                bottom: '2.54cm',
                left: '2.54cm',
                right: '2.54cm'
            }
        };
        await page.emulateMedia('screen');
        const pdf = await page.pdf(pdfConfig); // Return the pdf buffer. Useful for saving the file not to disk. 

        await browser.close();

        return pdf;
    }
}

(async() => {
    const url = 'https://ia601405.us.archive.org/18/items/alicesadventures19033gut/19033-h/19033-h.htm';
    const buffer = await Webpage.generatePDF(url);
})();