Examine source code of Zenhub Helper

{
  "name": "Zenhub Helper",
  "description": "This is a helper for Zenhub to maximize/restore Zenhub's working space.",
  "version": "1.0.1",
  "manifest_version": 2,
  "background": {
    "scripts": [
      "background.js"
    ]
  },
  "browser_action": {
    "default_icon": "maximize.png"
  },
  "permissions": [
    "activeTab",
    "tabs"
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "{95f714df-5c53-4c02-a134-5dd69943c8fb}"
    }
  }
}