Slow load times and flickering in Safari

I've been going through the react.dev docs and noticed that they feel sluggish:

https://github.com/reactjs/react.dev/assets/513444/0679274a-9325-4975-afea-b7e5315cffc2

I still see a little bit of flickering on Chrome, but I wouldn't consider it problematic there:

https://github.com/reactjs/react.dev/assets/513444/d1faca05-2606-4bf0-b680-c9f67e2b9fdf

The new site has a lot of interactive elements so it's not fair to compare it with the legacy site, but legacy is an order of magnitude faster:

https://github.com/reactjs/react.dev/assets/513444/fabe323d-e3d4-44d1-b5b7-f42bdcdabfa7

I think there are two separate issues:

• Some (larger) pages take several seconds to load
• Scrolling in Safari makes the screen flicker

This is on Safari Version 17.2.1 (19617.1.17.11.12) on Sonoma 14.2.1 (23C71). 2,6 GHz 6-Core Intel Core i7 MacBook Pro 16. Let me know if you need any other information to help debug.

Empieza reproduciendo el comportamiento informado en Safari 17.2.1 en las páginas de documentación más extensas de react.dev, utilizando las grabaciones enlazadas y comparándolo con Chrome y el sitio antiguo. Se considerará completado cuando las cargas lentas y el parpadeo al desplazarse en Safari se hayan resuelto o aislado claramente, y el comportamiento se haya comprobado en los navegadores indicados.