Examine source code of Vajehyab

{
  "name": "Vajehyab",
  "version": "1.2",
  "manifest_version": 2,
  "description": "Look up persian words using Vajehyab",
  "icons": {
    "48": "icon48.png",
    "128": "icon128.png"
  },
  "browser_action": {
    "default_icon": "icon.png"
  },
  "background": {
    "scripts": [
      "vajehyab.js"
    ]
  },
  "permissions": [
    "activeTab",
    "contextMenus"
  ],
  "author": "Zia Zafari"
}