Examine source code of NHComicDownloader

{
  "manifest_version": 2,
  "name": "NHComicDownloader",
  "description": "Downloads pages of a comic.",
  "version": "1.6",
  "browser_specific_settings": {
    "gecko": {
      "id": "NHComicDownloader@gmail.com"
    }
  },
  "permissions": [
    "tabs",
    "downloads",
    "activeTab"
  ],
  "browser_action": {
    "browser_style": true,
    "default_icon": {
      "16": "icons/NH_16.png",
      "32": "icons/NH_32.png"
    }
  },
  "background": {
    "scripts": [
      "background.js"
    ]
  },
  "content_scripts": [
    {
      "matches": [
        "*://nhentai.net/*"
      ],
      "js": [
        "NH.js"
      ]
    }
  ]
}