Examine source code of Mini Game New Tab

{
  "manifest_version": 2,
  "name": "Mini Game New Tab",
  "version": "1.0",
  "description": "Turn new tab into quick mini games like Sudoku, Flappy Bird, Word Guess.",
  "chrome_url_overrides": {
    "newtab": "newtab.html"
  },
  "permissions": [],
  "icons": {
    "128": "icon.png"
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{6551753f-936f-40f7-bb2f-40796f0b74cd}"
    }
  }
}