Examine source code of Realchill Startpage

{
  "manifest_version": 2,
  "name": "Realchill Startpage",
  "version": "0.2.5",
  "permissions": [
    "activeTab"
  ],
  "chrome_url_overrides": {
    "newtab": "index.html"
  },
  "browser_action": {
    "default_icon": "icon.png"
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "@realchill",
      "data_collection_permissions": {
        "required": [
          "none"
        ]
      }
    }
  }
}