Examine source code of Enhances the new tab

{
  "manifest_version": 2,
  "name": "New Tab Tools",
  "version": "1.0.0",
  "description": "Enhances the new tab page with a customizable grid of your favorite sites.",
  "permissions": [
    "storage"
  ],
  "chrome_url_overrides": {
    "newtab": "newtab.html"
  },
  "options_ui": {
    "page": "options.html",
    "open_in_tab": true
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{526f919c-e8e2-487e-b7cd-83cc2cfd904a}"
    }
  }
}