jargonFrontend & browser·Rendering and the browser pipeline
you added `will-change: transform` to make the animation smooth and the tab's memory use went up.
Layer promotion
Also calledwill-change, compositor layer
Giving an element its own compositor layer so it can be moved or faded without repainting anything around it. It is what makes a transform animation cheap, and it is requested explicitly with `will-change` or implicitly by properties like 3D transforms. Every layer costs GPU memory and adds work to the compositing step, so promoting dozens of elements makes scrolling worse rather than better.