Examine source code of manga-mark

{
  "manifest_version": 3,
  "name": "manga-mark",
  "version": "0.1",
  "description": "create bookmark on manga scan websites",
  "browser_specific_settings": {
    "gecko": {
      "id": "manga@mark",
      "strict_min_version": "42.0"
    }
  },
  "action": {
    "default_icon": {
      "16": "assets/images/icon.png"
    },
    "default_popup": "popup.html"
  },
  "content_scripts": [
    {
      "matches": [
        "https://mangadex.org/*"
      ],
      "js": [
        "script.js",
        "jquery.min.js"
      ],
      "run_at": "document_start"
    }
  ],
  "background": {
    "scripts": [
      "background-script.js"
    ]
  },
  "permissions": [
    "webNavigation",
    "storage",
    "webRequest",
    "history"
  ]
}