Examine source code of Flappy Bird

{
  "manifest_version": 3,
  "version": "0.1.2",
  "name": "Flappy Bird",
  "description": "Play Flappy Bird right from the toolbar for quick, addictive fun with simple controls and challenging gameplay.",
  "offline_enabled": true,
  "permissions": [
    "storage"
  ],
  "homepage_url": "https://webextension.org/listing/flappy-bird.html",
  "icons": {
    "16": "/data/icons/16.png",
    "32": "/data/icons/32.png",
    "48": "/data/icons/48.png",
    "64": "/data/icons/64.png",
    "128": "/data/icons/128.png",
    "256": "/data/icons/256.png",
    "512": "/data/icons/512.png"
  },
  "background": {
    "service_worker": "worker.js",
    "scripts": [
      "worker.js"
    ]
  },
  "action": {
    "default_popup": "/data/popup/index.html"
  },
  "commands": {
    "_execute_action": {}
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{2feb66e4-5c36-402f-8aa6-9511bf4232a3}",
      "strict_min_version": "128.0"
    }
  }
}