Examine source code of MangaBuff Navigation

{
  "manifest_version": 3,
  "name": "MangaBuff Navigation",
  "version": "1.1",
  "description": "Удобная навигация по главам на mangabuff.ru",
  "icons": {
    "48": "icon.png",
    "96": "icon.png",
    "128": "icon.png"
  },
  "content_scripts": [
    {
      "matches": [
        "*://mangabuff.ru/manga/*"
      ],
      "js": [
        "content.js"
      ]
    }
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "mangabuff-reader-nur-12345@firefox-addons.com",
      "data_collection_permissions": {
        "required": [
          "none"
        ]
      }
    }
  }
}