Note from 9 December 2021
Looks like @archdigestindia could improve #WebPerf for their readers and reduce bandwidth invoices…
- the photo is
564.5pxwide - but the
sizessays the image is full width - so the browser downloads an image
414 %bigger

Looks like @archdigestindia could improve #WebPerf for their readers and reduce bandwidth invoices…
564.5px widesizes says the image is full width414 % bigger
JPEG XL isn't useless; it is genuinely compelling technology for use cases beyond the Web. I'm just not personally convinced we need it in browsers…
The present and potential future of progressive image rendering
So if the browser manages to download 6 kB then stalls, then AVIF can produce a better result. But since the AVIF rendering is only two-pass, if the…
kliksphilip
JPEG VS AVIF - The Battle of Compression
In this super thorough study I test one single HD image and come to vast sweeping conclusions about JPEG XL and AVIF. But that's still one image comparison…
Should I please Lighthouse with modern image formats, or my visitors with progressive rendering of large images in my photography site? 🤔

Of course, this would be much easier with genaralized JPEG XL support, both modern and allowing progressive… 🤷♂️
Most mentions of the magical CSS object-fit: cover; in development tutorials should be accompanied by a warning: in most situations, it means the browser will download an image that is larger than required (at least in one direction), and optimization on the server side could be a better option.