Examine source code of Material-Null

{
  "name": "Material-Null",
  "description": "Another simple startpage.",
  "version": "1.3",
  "manifest_version": 2,
  "chrome_url_overrides": {
    "newtab": "index.html"
  },
  "icons": {
    "128": "bookmark.png"
  },
  "permissions": [
    "tabs"
  ]
}