How exactly was virtualization done — did you write your own wrapper or use a ready-made solution?

Frontend virtualization is usually implemented using ready-made solutions such as libraries like react-window or react-virtualized, which optimize rendering of long lists by displaying only the visible part of the elements in the DOM.

If the project is small or specific, you can write your own wrapper that tracks scrolling and dynamically adds/removes elements from the DOM.

For example, a simple wrapper can listen to scroll events and calculate which elements should be be visible, then render only those. But more often, proven libraries are used to avoid errors and improve performance.