preload.jsが見つからない問題　electron preload cannot load

const createWindow = () => {
  const mainWindow = new BrowserWindow({
    width: 600,
    height: 400,
    title: 'マイアプリ',
    webPreferences: {
      nodeIntegration: false,
      contextIsolation: true,
       preload: path.join(__dirname, 'preload.js'),
    },
  });

ここが大事

      nodeIntegration: false,
      contextIsolation: true,