Examine source code of Manga Curl 3D Reader

{
  "manifest_version": 2,
  "name": "Manga Curl 3D – Bibliothek",
  "version": "3.0.0",
  "description": "Manga & Buch Reader mit Bibliothek, persistenter Sprache, physikalischer Seitenanimation und Blätter-Curl.",
  "icons": {
    "16": "icons/icon16.png",
    "32": "icons/icon32.png",
    "48": "icons/icon48.png",
    "96": "icons/icon96.png",
    "128": "icons/icon128.png"
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "manga-curl-3d-reader@addon",
      "strict_min_version": "109.0"
    }
  },
  "permissions": [
    "storage",
    "unlimitedStorage",
    "activeTab",
    "tabs"
  ],
  "browser_action": {
    "default_icon": {
      "48": "icons/icon48.png"
    },
    "default_popup": "popup.html"
  },
  "background": {
    "scripts": [
      "background.js"
    ],
    "persistent": false
  },
  "content_scripts": [
    {
      "matches": [
        "*://*.mangadex.org/*",
        "*://*.mangareader.to/*",
        "*://*.mangapark.net/*",
        "*://*.mangasee123.com/*"
      ],
      "js": [
        "content.js"
      ],
      "css": [
        "content.css"
      ]
    }
  ]
}