Basic Chrome Extension using V3, using Electron supported APIs

background.js

console.log("Hello, I'm a service worker");

chrome.runtime.onInstalled.addListener((evt) => {
    console.log("Hello, I was just installed.");
});

chrome.runtime.onMessage.addListener((message, sender, reply) => {
    console.log(`Hello, I'm a service worker and I just received a message.`);
    reply("Hello sender, I received your message.");
});

content.js

console.log("I'm a content script, and I'm going to try to send a message to anyone that is listening.");
chrome.runtime.sendMessage("Hello from content script", function(response) {
    console.log(`I have receipted a response: ${response}`);
});

main.js

// Modules to control application life and create native browser window
const {app, BrowserWindow} = require('electron')
const path = require('path')

function createWindow () {
  // Create the browser window.
  const mainWindow = new BrowserWindow({
    width: 800,
    height: 600,
    webPreferences: {
      'session': 'persist:1234'
    }
  })

  // and load the index.html of the app.
  mainWindow.loadURL('https://www.electronjs.org')

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

  mainWindow.webContents.session.loadExtension(path.join(__dirname)).then((id) => {
    console.log(`Loaded extension ${id.name}`);
  })
}

// This method will be called when Electron has finished
// initialization and is ready to create browser windows.
// Some APIs can only be used after this event occurs.
app.whenReady().then(() => {
  createWindow()

  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 (BrowserWindow.getAllWindows().length === 0) createWindow()
  })
})

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

// In this file you can include the rest of your app's specific main process
// code. You can also put them in separate files and require them here.

manifest.json

{
  "name": "V3 service_worker test",
  "version": "1.0.0",
  "background": {
    "service_worker": "background.js"
  },
  "content_scripts": [
    {
      "matches": ["<all_urls>"],
      "js": ["content.js"],
      "run_at": "document_start"
    }
  ],
  "manifest_version": 3
}

package.json

{
  "name": "sassy-tennis-travel-a881u",
  "productName": "sassy-tennis-travel-a881u",
  "description": "My Electron application description",
  "keywords": [],
  "main": "./main.js",
  "version": "1.0.0",
  "author": "schetle",
  "scripts": {
    "start": "electron ."
  },
  "dependencies": {},
  "devDependencies": {
    "electron": "18.0.3"
  }
}