Examine source code of RickRollProtector

{
  "name": "RickRollProtector",
  "author": "fab3F",
  "version": "0.1.1.0",
  "description": "Du wirst nie wieder gerickrolled werden! Du bist immer auf der sicheren Seite, wenn du dieses Addon benutzt.",
  "permissions": [
    "storage",
    "scripting",
    "activeTab",
    "webRequest"
  ],
  "content_scripts": [
    {
      "js": [
        "background.js"
      ],
      "matches": [
        "https://*.youtube.com/*"
      ],
      "run_at": "document_start"
    },
    {
      "js": [
        "content.js"
      ],
      "matches": [
        "https://fab3f.github.io/rickrollprotector/*"
      ],
      "run_at": "document_start"
    },
    {
      "js": [
        "content.js"
      ],
      "matches": [
        "https://fab3F.github.io/rickrollprotector/*"
      ],
      "run_at": "document_start"
    }
  ],
  "icons": {
    "256": "icon.png"
  },
  "manifest_version": 2,
  "web_accessible_resources": [
    "error-firefox.html",
    "background.js",
    "content.js",
    "styles-firefox.css",
    "icon.png",
    "warn.js",
    "warn.png"
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "rickrollprotector@fab3F.github.io"
    }
  }
}