Examine source code of Derpi-New Tab

{
  "manifest_version": 2,
  "name": "Derpi-New Tab",
  "description": "A new tab page replacement featuring the latest pony wallpaper from Derpibooru",
  "version": "2.6.1",
  "browser_specific_settings": {
    "gecko": {
      "strict_min_version": "60.0"
    }
  },
  "permissions": [
    "https://derpibooru.org/",
    "https://derpicdn.net/"
  ],
  "optional_permissions": [
    "https://www.derpibooru.org/",
    "https://trixiebooru.org/",
    "cookies"
  ],
  "icons": {
    "16": "img/16.png",
    "32": "img/32.png",
    "48": "img/48.png",
    "128": "img/128.png",
    "256": "img/256.png"
  },
  "chrome_url_overrides": {
    "newtab": "index.html"
  }
}