main.js

const electron = require('electron')

// Initialise application
electron.app.whenReady().then(function() {

  // Create a new window
  var window = new electron.BrowserWindow({
    width: 1000,
    height: 1000,
    webPreferences: {
      nativeWindowOpen: true
    }
  });

  // Specify user agent so "download iCloud for Windows" banner doesn't appear
  electron.session.defaultSession.webRequest.onBeforeSendHeaders((details, callback) => {
    details.requestHeaders['User-Agent'] = "Mozilla/5.0 (Macintosh; Intel Mac OS X 10_14_5) AppleWebKit/605.1.15 (KHTML, like Gecko) Version/12.1.1 Safari/605.1.15";
    callback({
      cancel: false,
      requestHeaders: details.requestHeaders
    });
  });

  // Hide default top menu
  window.setMenu(null);

  // Make links set to open a new tab and window.open() open in the default browser instead of a new application window
  window.webContents.on("new-window", function(event, url) {
    event.preventDefault();

    if (url !== "about:blank#blocked") electron.shell.openExternal(url);
  });

  // Load the iCloud notes page
  window.loadURL("https://www.icloud.com");
});

// Quit when all windows closed
electron.app.on('window-all-closed', function() {
  electron.app.quit();
});