Examine source code of Quran Tab

{
  "update_url": "https://clients2.google.com/service/update2/crx",
  "name": "Quran Tab",
  "description": "Quran Tab is an Islamic new tab page that will keep you inspired by a verse from the Quran every time you open a new tab.",
  "version": "2.5.8",
  "manifest_version": 2,
  "permissions": [
    "notifications",
    "alarms"
  ],
  "background": {
    "scripts": [
      "background.js"
    ]
  },
  "icons": {
    "128": "icon128.png"
  },
  "chrome_url_overrides": {
    "newtab": "index.html"
  },
  "content_security_policy": "script-src 'self'"
}