Examine source code of Punycode Tooltips

{
  "manifest_version": 2,
  "name": "SHOW PUNYCODE FORMAT",
  "version": "1.0",
  "description": "Displays the URL of the currently active tab.",
  "permissions": [
    "activeTab"
  ],
  "browser_action": {
    "default_popup": "popup.html"
  },
  "content_scripts": [
    {
      "matches": [
        "<all_urls>"
      ],
      "js": [
        "tooltip.js"
      ]
    }
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "{fc396f57-2f1f-43e8-a8fb-ddfe89e7a1a4}"
    }
  }
}