Examine source code of Panelio

{
  "name": "Panelio",
  "version": "1.4resigned1",
  "description": "Quickly add any page you have discovered to your Panelio.me account.",
  "content_security_policy": "script-src 'self'; object-src 'self'",
  "background": {
    "scripts": [
      "background.js",
      "js/jquery-3.3.1.min.js",
      "js/validatetoken.js"
    ]
  },
  "browser_action": {
    "default_popup": "popup.html",
    "default_icon": {
      "16": "img/icon16_dis.png",
      "32": "img/icon32_dis.png",
      "48": "img/icon48_dis.png",
      "128": "img/icon128_dis.png"
    }
  },
  "icons": {
    "16": "img/icon16.png",
    "32": "img/icon32.png",
    "48": "img/icon48.png",
    "128": "img/icon128.png"
  },
  "manifest_version": 2,
  "permissions": [
    "activeTab",
    "tabs",
    "storage",
    "*://*/*",
    "webRequest"
  ],
  "applications": {
    "gecko": {
      "id": "addon@kartogram.co.uk"
    }
  }
}