Examine source code of QR Code Generator

{
  "manifest_version": 2,
  "name": "QR Code Generator",
  "description": "Minimal qrcode generator extension for firefox",
  "author": "Amin Esmkhani",
  "version": "1.0",
  "permissions": [
    "tabs",
    "<all_urls>"
  ],
  "browser_action": {
    "default_title": "QR Code Generator",
    "default_popup": "popup.html"
  },
  "web_accessible_resources": [
    "*"
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "{88d919e7-f148-4232-b540-941ab96881ce}"
    }
  }
}