Implementing Tic Tac Toe with 170mb of HTML - no JS or CSS

Published

2023-07-21 14:00

Collected

2026-07-01 11:02

---
id: 285
title: "Implementing Tic Tac Toe with 170mb of HTML - no JS or CSS"
source_domain: portswigger.net
source_url: "https://portswigger.net/blog/tic-tac-toe-in-html"
published_at: "2023-07-21 14:00"
tags: ["xss", "html", "chrome", "popover", "gareth-heyes", "experiment"]
phying_url: "https://phying.com/item/285"
lang: en
---

# Implementing Tic Tac Toe with 170mb of HTML - no JS or CSS

## Summary

Gareth Heyes builds Tic Tac Toe using only HTML and Chrome's experimental popover feature — no JavaScript or CSS — by brute-force generating 170MB of markup covering every possible game state.

## Intelligence Metadata

- **Sources:** portswigger.net
- **Published:** 2023-07-21 14:00
- **Original:** https://portswigger.net/blog/tic-tac-toe-in-html
- **Phying News:** https://phying.com/item/285