Any news on support for server-rendered css-in-js?

[DanielOrtel]

The css-in-js docs have the following statement:

Warning: CSS-in-JS libraries which require runtime JavaScript are not currently supported in Server Components. Using CSS-in-JS with newer React features like Server Components and Streaming requires library authors to support the latest version of React, including concurrent rendering.
We're working with the React team on upstream APIs to handle CSS and JavaScript assets with support for React Server Components and streaming architecture.

This was added with the release of the app router in v13, but since the introduction of server components and the app router, we've had a major react version bump and two major nextjs version bumps and there's still no news that I could find on the progress of this issue. It's clear as day that users want to use css-in-js and that css-in-js authors don't want to move away from the context api until a suitable replacement is possible, so there really should be some movement on this front.

It's not feasible for entire UI libraries and code bases built on css-in-js solutions to migrate to plain css solutions, and the lack of first-class support is still causing issues with adopting the app router and server components.