Memory leak in React component with useEffect and setTimeout in Node.js
I'm experiencing a memory leak in my React component that utilizes `setTimeout` inside a `useEffect`. The component fetches data from a Node.js backend, and I want to show a loading spinner while the data is being fetched. After the data is received, the spinner should disappear. However, if the component unmounts before the timeout completes, I end up with a console warning: `Warning: need to perform a React state update on an unmounted component.` Here's a simplified version of my code: ```javascript import React, { useEffect, useState } from 'react'; const DataFetchingComponent = () => { const [data, setData] = useState(null); const [loading, setLoading] = useState(true); useEffect(() => { const timer = setTimeout(() => { fetch('/api/data') .then(response => response.json()) .then(result => { setData(result); setLoading(false); }); }, 1000); return () => clearTimeout(timer); }, []); return ( <div> {loading ? <p>Loading...</p> : <p>Data: {JSON.stringify(data)}</p>} </div> ); }; export default DataFetchingComponent; ``` I've tried adding a cleanup function in my `useEffect`, but I still see the warning. The component unmounts normally, so I'm not sure why this is happening. Am I missing something in how I handle the async operation or the state updates? Should I be setting a flag or using a ref to prevent this warning? Any help would be appreciated!