Examine source code of John Xina

{
  "manifest_version": 2,
  "name": "John Xina",
  "version": "69.0",
  "description": "This addon replaces images with pictures of John Xina. Originally it replaced with Nicolas Cage images. But the future is now and our lord John Xina as come to save us :3",
  "applications": {
    "gecko": {
      "id": "federico@slongo.biz"
    }
  },
  "icons": {
    "32": "icon-32.png",
    "48": "icon-48.png",
    "64": "icon-64.png",
    "128": "icon-128.png"
  },
  "content_scripts": [
    {
      "matches": [
        "*://*/*"
      ],
      "js": [
        "johnify.js"
      ]
    }
  ],
  "permissions": [
    "storage"
  ],
  "options_ui": {
    "page": "options.html",
    "browser_style": true
  },
  "homepage_url": "https://github.com/FedericoSlongo/"
}