Examine source code of Zombie Buster Fun

{
  "manifest_version": 2,
  "name": "Zombie Buster Fun",
  "version": "1.0",
  "description": "Zombie Buster basic is a simple and fun game. Your job is to shoot incoming zombies by clicking and shooting.",
  "permissions": [],
  "browser_action": {
    "default_popup": "game.html",
    "default_icon": {
      "128": "images/player2.png"
    }
  },
  "icons": {
    "128": "images/player2.png"
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{e9d1a6b5-2348-4961-8f4b-688c64015cfc}"
    }
  }
}