Examine source code of WykopCan

{
  "manifest_version": 2,
  "name": "WykopCan",
  "description": "Oznacza pisowską propagandę na Wykopie!",
  "version": "2.3.4",
  "icons": {
    "448": "icons/icon.png"
  },
  "content_scripts": [
    {
      "matches": [
        "*://*.wykop.pl/*"
      ],
      "js": [
        "wykopcan.js"
      ]
    }
  ],
  "options_ui": {
    "page": "options.html"
  },
  "permissions": [
    "storage"
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "{72443b9e-70bc-40d5-80c3-466eaa3a6301}"
    }
  }
}