Examine source code of Docer Downloader

{
  "manifest_version": 2,
  "name": "Docer Downloader",
  "version": "1.24",
  "description": "A browser extension designed to facilitate the download of documents exceeding 1 MB on docer sites (docer.pl, docer.com.ar, docer.ar) without encountering payment requests.",
  "default_locale": "en",
  "permissions": [
    "tabs",
    "activeTab",
    "webRequest",
    "webRequestBlocking",
    "<all_urls>",
    "storage"
  ],
  "background": {
    "scripts": [
      "background.js"
    ],
    "persistent": true
  },
  "browser_action": {
    "default_popup": "popup.html",
    "default_icon": {
      "16": "images/icon16.png",
      "48": "images/icon48.png",
      "128": "images/icon128.png"
    }
  },
  "content_scripts": [
    {
      "matches": [
        "*://*.docer.pl/*",
        "*://*.docer.com.ar/*",
        "*://*.docer.ar/*"
      ],
      "js": [
        "contentScript.js"
      ],
      "run_at": "document_start"
    }
  ],
  "web_accessible_resources": [
    "config.json"
  ],
  "icons": {
    "16": "images/icon16.png",
    "48": "images/icon48.png",
    "128": "images/icon128.png"
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "sebastian@szelewi.cz",
      "strict_min_version": "79.0"
    }
  }
}