Первая программа Electron с React — Main process — окно и IPC

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

function createWindow() {
  const win = new BrowserWindow({
    width: 900,
    height: 600,
    webPreferences: {
      preload: path.join(__dirname, 'preload.js'),
      contextIsolation: true,
      nodeIntegration: false,
    },
  });

  // dev: Vite на localhost:5173; production: file://...
  if (process.env.VITE_DEV_SERVER_URL) {
    win.loadURL(process.env.VITE_DEV_SERVER_URL);
  } else {
    win.loadFile(path.join(__dirname, '../dist/index.html'));
  }
}

app.whenReady().then(createWindow);

ipcMain.handle('dialog:openFile', async () => {
  const { canceled, filePaths } = await dialog.showOpenDialog({
    properties: ['openFile'],
    filters: [{ name: 'Text', extensions: ['txt', 'md'] }],
  });
  if (canceled || filePaths.length === 0) return null;
  return filePaths[0];
});