Examine source code of UONE2X

{
  "manifest_version": 2,
  "name": "UONE2X",
  "version": "0.3.7",
  "icons": {
    "48": "/dist/48.png",
    "72": "/dist/72.png",
    "96": "/dist/96.png",
    "144": "/dist/144.png",
    "168": "/dist/168.png",
    "192": "/dist/192.png"
  },
  "content_scripts": [
    {
      "matches": [
        "https://*.next-engine.com/*",
        "https://*.next-engine.biz/*"
      ],
      "css": [
        "./dist/stylesheet/app.css"
      ],
      "js": [
        "./dist/javascript/app.min.js"
      ]
    }
  ],
  "options_ui": {
    "page": "options.html",
    "browser_style": true
  },
  "permissions": [
    "storage",
    "https://*.next-engine.com/"
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "{e6822533-e8f2-4d2e-b46c-6bdb07bb6ab8}"
    }
  }
}