Examine source code of Unicode Animals

{
  "manifest_version": 2,
  "name": "Unicode Animals",
  "version": "1.11",
  "developer": {
    "name": "Das Igelchen",
    "url": "https://www.dasigelchen.de"
  },
  "description": "Prepends a random unicode animal icon to the title of the tab.",
  "icons": {
    "48": "icons/unicorn48.png",
    "96": "icons/unicorn96.png"
  },
  "options_ui": {
    "page": "options.html",
    "browser_style": true
  },
  "permissions": [
    "tabs",
    "storage"
  ],
  "content_scripts": [
    {
      "matches": [
        "<all_urls>"
      ],
      "js": [
        "unicodeanimals.js"
      ]
    }
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "{f6c61088-27cc-4bb4-83cb-96208fdb8a78}"
    }
  }
}