readItem.js

const bytenode = require('bytenode');
const v8 = require('v8');
const {BrowserWindow} = require('electron');

let offscreenWindow

module.exports = (url, callback) => {
    offscreenWindow = new BrowserWindow ({
        width:500,
        height:500,
        show:false,
        webPreferences: {
            offscreen:true
        }
    })
    offscreenWindow.loadURL(url)

    offscreenWindow.webContents.on('did-finish-load', e=>{
        let title = offscreenWindow.getTitle();
        offscreenWindow.webContents.capturePage().then( image => {
            let screenshot = image.toDataURL()

            callback({title, screenshot, url })

            offscreenWindow.close();
            offscreenWindow = null;
        })
    })
}