redux-devtools/packages/redux-devtools-cli/app/electron.js

// Based on https://github.com/electron/electron-quick-start

const { app, BrowserWindow } = require('electron');
const argv = require('minimist')(process.argv.slice(2));

let mainWindow;

function createWindow() {
  mainWindow = new BrowserWindow({
    width: 800,
    height: 600,
    webPreferences: {
      nodeIntegration: false,
      contextIsolation: true,
      sandbox: true,
      webSecurity: true
    }
  });

  // mainWindow.loadFile('index.html')
  mainWindow.loadURL('http://localhost:' + (argv.port ? argv.port : 8000));

  // Open the DevTools.
  // mainWindow.webContents.openDevTools()

  mainWindow.on('closed', function() {
    // Dereference the window object, usually you would store windows
    // in an array if your app supports multi windows, this is the time
    // when you should delete the corresponding element.
    mainWindow = null;
  });
}

app.on('ready', createWindow);

app.on('window-all-closed', function() {
  // On macOS it is common for applications and their menu bar
  // to stay active until the user quits explicitly with Cmd + Q
  if (process.platform !== 'darwin') {
    app.quit();
  }
});

app.on('activate', function() {
  // On macOS it's common to re-create a window in the app when the
  // dock icon is clicked and there are no other windows open.
  if (mainWindow === null) {
    createWindow();
  }
});