r3f-perf
Easily monitor your ThreeJS performances.
svelte-inview
A Svelte action that monitors an element enters or leaves the viewport or a parent element. Performant and efficient thanks to using Intersection Observer under the hood.
sitespeed.io
sitespeed.io is an open-source tool for comprehensive web performance analysis, enabling you to test, monitor, and optimize your website’s speed using real browsers in various environments.