Examine source code of YFull Helper

{
  "manifest_version": 3,
  "name": "__MSG_extensionName__",
  "version": "4.2",
  "default_locale": "en",
  "browser_specific_settings": {
    "gecko": {
      "id": "{8e677581-5528-429f-bb1d-069194188a2f}"
    }
  },
  "icons": {
    "16": "icons/YF16.png",
    "20": "icons/YF20.png",
    "32": "icons/YF32.png",
    "48": "icons/YF48.png",
    "64": "icons/YF64.png",
    "128": "icons/YF128.png"
  },
  "description": "__MSG_extensionDescription__",
  "permissions": [
    "storage"
  ],
  "host_permissions": [
    "*://*.yfull.com/*",
    "https://genetic-genealogy.info/*"
  ],
  "content_scripts": [
    {
      "matches": [
        "*://*.yfull.com/*"
      ],
      "js": [
        "scripts/iso_country_codes.js",
        "scripts/utils.js",
        "scripts/content_script.js"
      ]
    }
  ],
  "action": {
    "default_title": "__MSG_extensionName__",
    "default_popup": "popupMenu.html"
  },
  "background": {
    "scripts": [
      "scripts/service_worker.js"
    ]
  }
}