Have you had tasks to optimize the performance of large lists? How did you solve them?

Optimizing large lists often involves reducing the number of elements rendered at the same time to decrease DOM load and improve performance.

Main approaches:

• Virtualization (virtual scroll) — only visible list items and a small buffer above and below are rendered. For example, libraries like react-window or react-virtualized.
• Pagination — splitting the list into pages, loading and displaying only the current page's items.
• Lazy loading — loading items as the user scrolls.
• Render optimization — using React.memo, shouldComponentUpdate, and keys to minimize re-renders.

Example with virtualization in React using react-window:

import { FixedSizeList as List } from 'react-window';

const Row = ({ index, style }) => (
  <div style={style}>Item #{index}</div>
);

<List
  height={500}
  itemCount={10000}
  itemSize={35}
  width={300}
>
  {Row}
</List>

This approach allows efficient handling of very large lists without overloading the browser.