Examine source code of Startify

{
  "manifest_version": 2,
  "name": "Startify",
  "description": "A customizable and beautiful new tab page for your browser.",
  "version": "1.5.2",
  "icons": {
    "16": "icons/16.png",
    "32": "icons/32.png",
    "48": "icons/48.png",
    "128": "icons/128.png"
  },
  "default_locale": "en",
  "browser_specific_settings": {
    "gecko": {
      "id": "{d5e5fe42-da08-4573-8ffd-6075ae68c834}"
    }
  },
  "permissions": [
    "storage",
    "unlimitedStorage",
    "activeTab",
    "downloads",
    "https://*/*",
    "http://*/*",
    "https://api.weatherapi.com/"
  ],
  "background": {
    "scripts": [
      "background.js"
    ]
  },
  "chrome_url_overrides": {
    "newtab": "newtab.html"
  }
}