It takes a long time for a new CSS feature or improvement to progress from an initial draft to a fully-supported and stable CSS feature that developers can use. JavaScript-based polyfills can be used as a substitute for the lack of browser support in order to use new CSS features before they’re officially implemented. But they are flawed in most cases. For example, scrollsnap-polyfill is one of several polyfills that can be used to fix browser support inconsistencies for the CSS Scroll Snap specification.

https://www.smashingmagazine.com/2020/03/practical-overview-css-houdini/