Examine source code of NewTab Homepage

{
  "manifest_version": 2,
  "name": "New Tab",
  "version": "1.0",
  "permissions": [
    "webNavigation",
    "browserSettings"
  ],
  "chrome_url_overrides": {
    "newtab": "newtab.html"
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{f7dc98cf-d615-4fe0-a65a-b0603de9f890}"
    }
  }
}