Examine source code of AntiRick

{
  "content_scripts": [
    {
      "js": [
        "background.js"
      ],
      "matches": [
        "https://*.youtube.com/*"
      ],
      "run_at": "document_start"
    }
  ],
  "name": "AntiRick",
  "version": "1.1",
  "description": "Increase your web-browsing security by ATTEMPTING to block rick rolls.",
  "manifest_version": 2,
  "web_accessible_resources": [
    "warn/warn.html"
  ],
  "permissions": [
    "storage"
  ],
  "icons": {
    "16": "icons/icon16.png",
    "48": "icons/icon48.png",
    "128": "icons/icon128.png"
  }
}