Examine source code of React New Tab

{
  "manifest_version": 2,
  "name": "React new tab",
  "version": "0.5.0",
  "author": "Ramkumar K R",
  "chrome_url_overrides": {
    "newtab": "index.html"
  },
  "description": "A Fast and Light weight new tab",
  "permissions": [
    "bookmarks",
    "storage",
    "cookies",
    "contextualIdentities"
  ],
  "options_ui": {
    "page": "options.html",
    "open_in_tab": true,
    "browser_style": true
  },
  "web_accessible_resources": [
    "/images/folder.png"
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "@react-new-tab-firefox"
    }
  }
}