Virtualizing Dynamic Lists and Responsive Grids Without Offset Tables or Size Estimation

In this article, I'd like to share my approach to virtualizing lists with items of unknown height. Most existing virtualization libraries solve this problem by estimating item sizes, measuring the rendered elements, and continuously correcting those estimates as more information becomes available. Here I'd like to describe a method that takes a different direction. Instead of relying on accumulated item offsets, it maps item indices directly to the scrollbar position. This makes it possible to d