Examine source code of QRtag.net

{
  "name": "QRtag.net - The QR Code Generator",
  "short_name": "QRtag.net",
  "description": "Generates an QR Code of the current page.",
  "version": "1.0.5",
  "manifest_version": 2,
  "icons": {
    "16": "icon_16.png",
    "48": "icon_48.png",
    "128": "icon_128.png",
    "256": "icon_256.png",
    "512": "icon_512.png"
  },
  "browser_action": {
    "default_icon": "icon_128.png",
    "default_popup": "popup.html"
  },
  "permissions": [
    "activeTab"
  ]
}