[cnotv]

It IS grid, lvl 3. You can achieve it with:

  display: grid;

  grid-template-rows: masonry;

This is however limited to webkit. I implemented it and ditched in October 2023 already for my private news feed in gallery mode.

[qingcharles]

What do you use instead?

I have it behind a CSS test for the existence of the CSS property so it is only enabled if the browser supports it.