Examine source code of QR Code

{
  "manifest_version": 2,
  "name": "QR Code",
  "version": "1.4",
  "description": "Adds a button to the address bar to get the current url as a qr code",
  "icons": {
    "48": "icon.svg",
    "96": "icon.svg"
  },
  "permissions": [
    "activeTab",
    "menus"
  ],
  "page_action": {
    "show_matches": [
      "<all_urls>"
    ],
    "browser_style": true,
    "default_icon": "icon.svg",
    "default_title": "QR Code",
    "default_popup": "popup.html"
  },
  "background": {
    "scripts": [
      "background.js"
    ]
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{a218c3db-51ef-4170-804b-eb053fc9a2cd}"
    }
  }
}