Examine source code of AZ BS Filter

{
  "manifest_version": 2,
  "name": "A-Z BS Filter",
  "version": "0.4.0",
  "description": "Filter Amazon Kindle Best Seller lists to hide previously seen items and low-rated books",
  "icons": {
    "16": "icons/icon-16.png",
    "48": "icons/icon-48.png",
    "128": "icons/icon-128.png"
  },
  "permissions": [
    "storage",
    "activeTab",
    "*://*.amazon.com/*",
    "*://*.amazon.com.au/*",
    "*://*.amazon.com.be/*",
    "*://*.amazon.com.br/*",
    "*://*.amazon.ca/*",
    "*://*.amazon.cn/*",
    "*://*.amazon.eg/*",
    "*://*.amazon.fr/*",
    "*://*.amazon.de/*",
    "*://*.amazon.in/*",
    "*://*.amazon.it/*",
    "*://*.amazon.co.jp/*",
    "*://*.amazon.com.mx/*",
    "*://*.amazon.nl/*",
    "*://*.amazon.pl/*",
    "*://*.amazon.sa/*",
    "*://*.amazon.sg/*",
    "*://*.amazon.es/*",
    "*://*.amazon.se/*",
    "*://*.amazon.com.tr/*",
    "*://*.amazon.ae/*",
    "*://*.amazon.co.uk/*"
  ],
  "background": {
    "scripts": [
      "background.js"
    ],
    "persistent": false
  },
  "content_scripts": [
    {
      "matches": [
        "*://*.amazon.com/gp/bestsellers/digital-text/*",
        "*://*.amazon.com/gp/bestsellers/books/*",
        "*://*.amazon.com/*/zgbs/digital-text/*",
        "*://*.amazon.com/*/zgbs/books/*",
        "*://*.amazon.com.au/gp/bestsellers/digital-text/*",
        "*://*.amazon.com.au/gp/bestsellers/books/*",
        "*://*.amazon.com.au/*/zgbs/digital-text/*",
        "*://*.amazon.com.au/*/zgbs/books/*",
        "*://*.amazon.com.be/gp/bestsellers/digital-text/*",
        "*://*.amazon.com.be/gp/bestsellers/books/*",
        "*://*.amazon.com.be/*/zgbs/digital-text/*",
        "*://*.amazon.com.be/*/zgbs/books/*",
        "*://*.amazon.com.br/gp/bestsellers/digital-text/*",
        "*://*.amazon.com.br/gp/bestsellers/books/*",
        "*://*.amazon.com.br/*/zgbs/digital-text/*",
        "*://*.amazon.com.br/*/zgbs/books/*",
        "*://*.amazon.ca/gp/bestsellers/digital-text/*",
        "*://*.amazon.ca/gp/bestsellers/books/*",
        "*://*.amazon.ca/*/zgbs/digital-text/*",
        "*://*.amazon.ca/*/zgbs/books/*",
        "*://*.amazon.cn/gp/bestsellers/digital-text/*",
        "*://*.amazon.cn/gp/bestsellers/books/*",
        "*://*.amazon.cn/*/zgbs/digital-text/*",
        "*://*.amazon.cn/*/zgbs/books/*",
        "*://*.amazon.eg/gp/bestsellers/digital-text/*",
        "*://*.amazon.eg/gp/bestsellers/books/*",
        "*://*.amazon.eg/*/zgbs/digital-text/*",
        "*://*.amazon.eg/*/zgbs/books/*",
        "*://*.amazon.fr/gp/bestsellers/digital-text/*",
        "*://*.amazon.fr/gp/bestsellers/books/*",
        "*://*.amazon.fr/*/zgbs/digital-text/*",
        "*://*.amazon.fr/*/zgbs/books/*",
        "*://*.amazon.de/gp/bestsellers/digital-text/*",
        "*://*.amazon.de/gp/bestsellers/books/*",
        "*://*.amazon.de/*/zgbs/digital-text/*",
        "*://*.amazon.de/*/zgbs/books/*",
        "*://*.amazon.in/gp/bestsellers/digital-text/*",
        "*://*.amazon.in/gp/bestsellers/books/*",
        "*://*.amazon.in/*/zgbs/digital-text/*",
        "*://*.amazon.in/*/zgbs/books/*",
        "*://*.amazon.it/gp/bestsellers/digital-text/*",
        "*://*.amazon.it/gp/bestsellers/books/*",
        "*://*.amazon.it/*/zgbs/digital-text/*",
        "*://*.amazon.it/*/zgbs/books/*",
        "*://*.amazon.co.jp/gp/bestsellers/digital-text/*",
        "*://*.amazon.co.jp/gp/bestsellers/books/*",
        "*://*.amazon.co.jp/*/zgbs/digital-text/*",
        "*://*.amazon.co.jp/*/zgbs/books/*",
        "*://*.amazon.com.mx/gp/bestsellers/digital-text/*",
        "*://*.amazon.com.mx/gp/bestsellers/books/*",
        "*://*.amazon.com.mx/*/zgbs/digital-text/*",
        "*://*.amazon.com.mx/*/zgbs/books/*",
        "*://*.amazon.nl/gp/bestsellers/digital-text/*",
        "*://*.amazon.nl/gp/bestsellers/books/*",
        "*://*.amazon.nl/*/zgbs/digital-text/*",
        "*://*.amazon.nl/*/zgbs/books/*",
        "*://*.amazon.pl/gp/bestsellers/digital-text/*",
        "*://*.amazon.pl/gp/bestsellers/books/*",
        "*://*.amazon.pl/*/zgbs/digital-text/*",
        "*://*.amazon.pl/*/zgbs/books/*",
        "*://*.amazon.sa/gp/bestsellers/digital-text/*",
        "*://*.amazon.sa/gp/bestsellers/books/*",
        "*://*.amazon.sa/*/zgbs/digital-text/*",
        "*://*.amazon.sa/*/zgbs/books/*",
        "*://*.amazon.sg/gp/bestsellers/digital-text/*",
        "*://*.amazon.sg/gp/bestsellers/books/*",
        "*://*.amazon.sg/*/zgbs/digital-text/*",
        "*://*.amazon.sg/*/zgbs/books/*",
        "*://*.amazon.es/gp/bestsellers/digital-text/*",
        "*://*.amazon.es/gp/bestsellers/books/*",
        "*://*.amazon.es/*/zgbs/digital-text/*",
        "*://*.amazon.es/*/zgbs/books/*",
        "*://*.amazon.se/gp/bestsellers/digital-text/*",
        "*://*.amazon.se/gp/bestsellers/books/*",
        "*://*.amazon.se/*/zgbs/digital-text/*",
        "*://*.amazon.se/*/zgbs/books/*",
        "*://*.amazon.com.tr/gp/bestsellers/digital-text/*",
        "*://*.amazon.com.tr/gp/bestsellers/books/*",
        "*://*.amazon.com.tr/*/zgbs/digital-text/*",
        "*://*.amazon.com.tr/*/zgbs/books/*",
        "*://*.amazon.ae/gp/bestsellers/digital-text/*",
        "*://*.amazon.ae/gp/bestsellers/books/*",
        "*://*.amazon.ae/*/zgbs/digital-text/*",
        "*://*.amazon.ae/*/zgbs/books/*",
        "*://*.amazon.co.uk/gp/bestsellers/digital-text/*",
        "*://*.amazon.co.uk/gp/bestsellers/books/*",
        "*://*.amazon.co.uk/*/zgbs/digital-text/*",
        "*://*.amazon.co.uk/*/zgbs/books/*"
      ],
      "js": [
        "content.js"
      ],
      "run_at": "document_idle"
    }
  ],
  "browser_action": {
    "default_popup": "popup.html",
    "default_icon": {
      "16": "icons/icon-16.png",
      "48": "icons/icon-48.png",
      "128": "icons/icon-128.png"
    },
    "default_title": "A-Z BS Filter"
  },
  "options_ui": {
    "page": "options.html",
    "open_in_tab": true
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "azbs.filter@weisnobody.com",
      "strict_min_version": "109.0",
      "data_collection_permissions": {
        "required": [
          "none"
        ]
      }
    }
  }
}