Examine source code of ICMP Types & Codes

{
  "manifest_version": 2,
  "name": "ICMP Types & Codes",
  "version": "1.0",
  "description": "Offline reference for ICMP types and codes.",
  "permissions": [
    "clipboardWrite"
  ],
  "browser_action": {
    "default_popup": "popup.html"
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "icmp_types_codes@xai.example"
    }
  }
}