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Hoài Nhớ ( Nick )
Hoài Nhớ ( Nick )

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Open-source React DevTools extension for spotting performance and state issues in real time

Debugging React apps often feels like detective work — the symptoms are obvious but the root cause still takes too long to find. I kept seeing the same patterns: missing effect cleanups, accidental state mutations, and components re-rendering far too often.
So I built an open‑source Chrome DevTools extension that hooks into the React Fiber tree and flags those issues while you’re developing.

What it covers

  • State & UI issues: direct state mutation, missing keys, index-as-key
  • Render tracking: highlights components with excessive re-renders
  • Effects: missing cleanup and suspicious dependencies
  • CLS monitoring in real time
  • Timeline view of React events
  • Memory monitoring for potential leaks
  • Redux: state tree view + manual action dispatch

How it works

  • Reads from React DevTools global hook / Fiber tree
  • Analysis throttled to reduce overhead
  • Traversal capped to keep it lightweight
  • Only injects when DevTools panel is opened

Install
npx react-debugger
Then load unpacked in chrome://extensions.

Links
Npm: https://www.npmjs.com/package/react-debugger
Opensourced: https://github.com/hoainho/react-debugger-extension
Demo: https://jumpshare.com/share/Z1Hd1eS69yNqrVKn0qzw

Feedback I’m looking for

  1. Are the effect warnings useful or too noisy in real projects?
  2. What’s a reasonable default threshold for “too many re-renders”?
  3. Any other React debugging signals you wish existed in DevTools?

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