Examine source code of World Nations Quiz

{
  "manifest_version": 2,
  "name": "World Nations Quiz",
  "version": "1.0",
  "description": "Famous countries quiz from Vietnamese clues.",
  "icons": {
    "48": "globe_icon.png"
  },
  "browser_action": {
    "default_popup": "index.html",
    "default_title": "World Nations Quiz"
  },
  "permissions": [],
  "browser_specific_settings": {
    "gecko": {
      "id": "{40996586-1ad2-476b-8a27-c710f07ce6ac}",
      "data_collection_permissions": {
        "required": [
          "none"
        ],
        "optional": []
      }
    }
  }
}