Examine source code of URL QR Code Generator

{
  "description": "Adds a browser action icon to the toolbar. Click the button to generate a QR code for the current URL.",
  "manifest_version": 2,
  "name": "QR Code Generator",
  "version": "1.1",
  "homepage_url": "https://github.com/RiccardoZaffalon/qrcode-generator.git",
  "icons": {
    "48": "qr_code.b5e05a23.png"
  },
  "permissions": [
    "activeTab"
  ],
  "page_action": {
    "show_matches": [
      "<all_urls>"
    ],
    "default_icon": "qr_code.b5e05a23.png",
    "default_title": "Get QR Code",
    "default_popup": "qr_code.deaaa535.html"
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{ca9619f3-cfc9-42be-ae22-d9c6a92d4d3c}"
    }
  }
}