Image lazy loading

[Gummibeer]

Browser-level image lazy-loading for the web

This post covers the loading attribute and how it can be used to control the loading of images.

web.dev

Does anyone see a way for a polyfill? The only way I see is to parse user agent on server side and deliver different HTML!?
The problem I see is that JS lazy loading is based on attribute replacement but the browser one uses a regular IMG tag with an additional attribute - like script async/defer. It's what I wished for - but it will take years until it's supported in major browsers.