Examine source code of Amazon Alternatives

{
  "manifest_version": 2,
  "name": "Amazon Alternatives",
  "short_name": "amazon_alts",
  "description": "Find a book or something else in Amazon, et fetch it elswehere!",
  "homepage_url": "https://github.com/amazon-alternatives/extension",
  "version": "1.12.10",
  "author": "Adrian Tombu <adrian@otso.fr>",
  "icons": {
    "48": "assets/icon-48.png",
    "96": "assets/icon-96.png"
  },
  "browser_action": {
    "default_icon": {
      "16": "assets/icon-16.png",
      "32": "assets/icon-32.png",
      "64": "assets/icon-64.png"
    },
    "default_title": "Amazon Alternatives",
    "default_popup": "popup.html"
  },
  "content_scripts": [
    {
      "matches": [
        "*://*.amazon.fr/*",
        "*://*.amazon.com/*",
        "*://*.amazon.co.uk/*",
        "*://*.amazon.com.mx/*",
        "*://*.amazon.co.jp/*",
        "*://*.amazon.it/*",
        "*://*.amazon.in/*",
        "*://*.amazon.es/*",
        "*://*.amazon.cn/*",
        "*://*.amazon.ca/*",
        "*://*.amazon.com.br/*",
        "*://*.amazon.de/*",
        "*://*.amazon.com.au/*"
      ],
      "js": [
        "app.js"
      ],
      "css": [
        "styles.css"
      ],
      "run_at": "document_end"
    }
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "{69085149-a34e-4f46-b6ef-ff4ea64bce4c}"
    }
  }
}