Examine source code of John's URL Sender

{
  "manifest_version": 2,
  "name": "URL Sender",
  "version": "1.1",
  "description": "Send current page URL to a configurable API endpoint",
  "permissions": [
    "activeTab",
    "storage"
  ],
  "browser_action": {
    "default_popup": "popup.html",
    "default_icon": {
      "512": "icon.png"
    }
  },
  "browser_specific_settings": {
    "gecko": {
      "data_collection_permissions": {
        "required": [
          "none"
        ]
      },
      "id": "{64a9e60a-1374-4355-b57b-8a3439de4a1b}"
    }
  },
  "icons": {
    "512": "icon.png"
  }
}