Examine source code of Random Joke Generator Fun

{
  "manifest_version": 2,
  "name": "Random Joke Generator",
  "version": "1.0",
  "description": "Random Joke Generator is a fun widget. It fetches a random joke from an API and displays it on the widget popup.",
  "permissions": [],
  "browser_action": {
    "default_popup": "game.html",
    "default_icon": {
      "128": "images/jokerfun-logo.png"
    }
  },
  "icons": {
    "128": "images/jokerfun-logo.png"
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{c8df9914-6831-441c-af6b-3e7d9426600a}"
    }
  }
}