Examine source code of Flappy Bird Basic Fun

{
  "manifest_version": 2,
  "name": "Flappy Bird Basic Fun",
  "version": "1.0",
  "description": "Flappy Bird Basic Fun is a simple but fully functional game utility with many attractive difficulty levels",
  "permissions": [],
  "browser_action": {
    "default_popup": "game.html",
    "default_icon": {
      "128": "images/flapy-logo.png"
    }
  },
  "icons": {
    "128": "images/flapy-logo.png"
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{a85fb2c1-82a9-4261-9032-0fe9a5e52f96}"
    }
  }
}