Philip Walton published a new article where he do a deep dive into improving website performance with a technique he's calling Idle Until Urgent.
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A modest JavaScript framework for the HTML you already have. Stimulus is a JavaScript framework with modest ambitions. It doesn’t seek to take over your entire front-end—in fact, it’s not concerned with rendering HTML at all. Instead, it’s designed to augment your HTML with just enough behavior to make it shine
BarbaJS
Create badass fluid and smooth transitions between your website’s pages.
Zdog
Zdog is a 3D JavaScript engine for Canvas and SVG. With Zdog, you can design and render simple 3D models on the Web. Zdog is a pseudo-3D engine. Its geometries exist in 3D space, but are rendered as flat shapes.