Examine source code of Genius Start Page

{
  "manifest_version": 2,
  "name": "Genius Start Page",
  "short_name": "Genius Tab",
  "version": "1.0.0",
  "description": "A minimal, complex and customizable browser start page extension",
  "author": "Ufuayk",
  "homepage_url": "https://github.com/ufuayk",
  "browser_specific_settings": {
    "gecko": {
      "id": "genius-start-page@ufuayk.github.io",
      "strict_min_version": "79.0"
    }
  },
  "browser_action": {
    "default_popup": "popup.html",
    "default_icon": {
      "16": "icons/icon16.png",
      "48": "icons/icon48.png",
      "128": "icons/icon128.png"
    },
    "default_title": "Genius Start Page"
  },
  "background": {
    "scripts": [
      "background.js"
    ]
  },
  "chrome_url_overrides": {
    "newtab": "genius-start-page/index.html"
  },
  "permissions": [
    "storage",
    "tabs",
    "https://ufuk.bearblog.dev/*"
  ],
  "icons": {
    "16": "icons/icon16.png",
    "48": "icons/icon48.png",
    "128": "icons/icon128.png"
  },
  "content_security_policy": "script-src 'self'; object-src 'self'"
}