Examine source code of Numer - Number Converter

{
  "manifest_version": 2,
  "name": "Numer - Number Converter",
  "version": "1.0.0",
  "description": "Easily convert English numbers to Persian (Farsi) or Arabic numerals with this simple and fast online tool.",
  "browser_action": {
    "default_popup": "popup.html",
    "default_icon": {
      "16": "icons/icon16.png",
      "48": "icons/icon48.png",
      "128": "icons/icon128.png"
    }
  },
  "icons": {
    "16": "icons/icon16.png",
    "48": "icons/icon48.png",
    "128": "icons/icon128.png"
  },
  "permissions": [],
  "browser_specific_settings": {
    "gecko": {
      "id": "{7fe81008-9f9c-4bf7-9628-68f2ebab350d}"
    }
  }
}