The case for live previews

Static thumbnails are cheap and they lie. Half the components worth having are interactive: they respond to a cursor, they animate on scroll, they change under a keyboard.

Rendering every card in its own sandboxed iframe costs more, but it means what you scroll past is the actual component, running, at a real breakpoint.

It also keeps authors honest. A component that only looks good in a hand-cropped screenshot has nowhere to hide when the frame renders it live at 1200 pixels wide.