Examine source code of Google Search Maps Button

{
  "manifest_version": 2,
  "name": "Google Search Maps Button",
  "version": "1.2.4",
  "description": "Adds back the Maps button to Google search pages and makes the search result map images clickable again for seamless navigation.",
  "icons": {
    "16": "images/icon16.png",
    "48": "images/icon48.png",
    "128": "images/icon128.png"
  },
  "permissions": [
    "activeTab"
  ],
  "content_scripts": [
    {
      "matches": [
        "https://www.google.com/search*",
        "https://www.google.co.uk/search*",
        "https://www.google.co.jp/search*",
        "https://www.google.com.au/search*",
        "https://www.google.at/search*",
        "https://www.google.be/search*",
        "https://www.google.bg/search*",
        "https://www.google.hr/search*",
        "https://www.google.cy/search*",
        "https://www.google.cz/search*",
        "https://www.google.dk/search*",
        "https://www.google.ee/search*",
        "https://www.google.fi/search*",
        "https://www.google.fr/search*",
        "https://www.google.de/search*",
        "https://www.google.gr/search*",
        "https://www.google.hu/search*",
        "https://www.google.ie/search*",
        "https://www.google.it/search*",
        "https://www.google.lv/search*",
        "https://www.google.lt/search*",
        "https://www.google.lu/search*",
        "https://www.google.mt/search*",
        "https://www.google.nl/search*",
        "https://www.google.pl/search*",
        "https://www.google.pt/search*",
        "https://www.google.ro/search*",
        "https://www.google.sk/search*",
        "https://www.google.si/search*",
        "https://www.google.es/search*",
        "https://www.google.se/search*",
        "https://www.google.is/search*",
        "https://www.google.li/search*",
        "https://www.google.no/search*",
        "https://www.google.sm/search*",
        "https://www.google.ch/search*",
        "https://www.google.com.ua/search*",
        "https://www.google.rs/search*",
        "https://www.google.me/search*",
        "https://www.google.ba/search*",
        "https://www.google.mk/search*",
        "https://www.google.md/search*",
        "https://www.google.by/search*",
        "https://www.google.ad/search*",
        "https://www.google.mc/search*"
      ],
      "js": [
        "src/addMapsBtn.js"
      ]
    }
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "{884f845b-914f-4069-ad5b-b8bf870249fc}"
    }
  }
}