There’s a new term in town: soft navigations . Basically it means “single page app” (SPA) style navigations where page stuff changes, and the URL changes, but the browser didn’t do a traditional full-reload thing. I like the term in the sense that it sounds like a light insult. Whattaya too weak, child , to do a proper page load? Whattaya soft? Anyway the point of it is so that the browser itself has a way to detect these things, and testing Core Web Vitals is the entire reason. That feels like kind of a light reason to introduce a whole new API, but Google invented Core Web Vitals and their in-house initiatives like that get the juice. And the out-of-house initiatives sometimes get the boot. So when there is a cool new image format in town, like JPEG XL , that isn’t from Google, things get weird. Declan Chidlow wrote about this in JPEG XL and Google’s War Against It . Google invented WebP in-house, so people feel it’s protected over better technology.…