nfs/main.js

const url = require('url').format({
    protocol: 'file',
    slashes: true,
    pathname: require('path').join(__dirname, 'index.html')
});

const { app, BrowserWindow } = require('electron');

let win;

const createWindow = () => {
    win = new BrowserWindow({
        width: 500,
        height: 850
    });

    win.loadURL(url);

    win.on('closed', () => win = null)
}

app.on('ready', createWindow);

app.on('window-all-closed', () => app.quit())