Examine source code of Hai Phong Tours

{
  "name": "Hai Phong Tours",
  "version": "0.0.1",
  "manifest_version": 2,
  "description": "Hai Phong Tours Quick Access",
  "homepage_url": "https://haiphongtours.com",
  "icons": {
    "16": "icons/icon16.png",
    "19": "icons/icon19.png",
    "48": "icons/icon48.png",
    "128": "icons/icon128.png"
  },
  "default_locale": "en",
  "background": {
    "page": "src/bg/background.html",
    "persistent": true
  }
}