Examine source code of Subdomain Finder

{
  "manifest_version": 3,
  "name": "Subdomain Enumeration",
  "version": "2.0.1",
  "description": "Enumerates subdomains, directories, shows website IP, and checks for robots.txt",
  "permissions": [
    "activeTab",
    "storage",
    "tabs"
  ],
  "host_permissions": [
    "<all_urls>"
  ],
  "action": {
    "default_popup": "popup.html",
    "default_icon": {
      "48": "icons/icon48.png"
    }
  },
  "icons": {
    "48": "icons/icon48.png",
    "96": "icons/icon96.png",
    "128": "icons/icon128.png"
  },
  "background": {
    "type": "module",
    "scripts": [
      "background.js"
    ]
  },
  "web_accessible_resources": [
    {
      "resources": [
        "thank-you.html"
      ],
      "matches": [
        "<all_urls>"
      ]
    }
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "{a6d836ef-ea8f-4c89-8074-c90e70f8735c}"
    }
  }
}