Show HN: A Chrome extension that highlights one sentence at a time while reading

While reading long-form articles online, I often wanted to quickly recover my place — whether I got distracted or briefly looked away to check a concept or term. I thought it would be helpful to have something that marks your current position at the sentence level, but I couldn’t find any tool that did that — so I made a Chrome extension for it.

I implemented an algorithm that traverses the DOM tree to detect sentence boundaries, handling inline tags like <a>, <strong>, or <em> without breaking the flow. The goal was to ensure sentence detection works reliably, even within real-world, messy HTML.

This was also my first time working with JavaScript and TypeScript, so there may be rough edges. I’d love any feedback — about implementation, performance, or general usability.

GitHub: https://github.com/hamsteak1488/focus-anchor

Chrome Web Store: https://chromewebstore.google.com/detail/focus-anchor/fbgkhg...