Examine source code of Tabplanner

{
  "short_name": "Tabplanner",
  "manifest_version": 2,
  "version": "1.0.1",
  "name": "Tabplanner",
  "chrome_url_overrides": {
    "newtab": "index.html"
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{360c9ef2-25ca-4695-add8-85e23ffc00fe}"
    }
  }
}