Examine source code of Jack

{
  "name": "Jack",
  "description": "Manage temporary e-mails addresses and passwords.",
  "manifest_version": 2,
  "version": "1.3",
  "author": "Augustin LAOUAR",
  "icons": {
    "48": "icons/jack-2-min.png"
  },
  "browser_action": {
    "default_area": "navbar",
    "default_icon": "icons/jack-2-min.png",
    "default_popup": "html/login.html",
    "default_title": "Jack"
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "jacksmails@harrouchi.com"
    }
  },
  "permissions": [
    "storage",
    "tabs",
    "<all_urls>",
    "contextMenus",
    "activeTab",
    "alarms"
  ],
  "background": {
    "page": "/html/background.html",
    "persistent": true
  },
  "content_scripts": [
    {
      "matches": [
        "<all_urls>"
      ],
      "js": [
        "/js/content/refresh_timer.js"
      ]
    }
  ]
}