Feedback page hydration problem

[slorber]

🐛 Bug Report

When accessed directly with a "deep link", there's an hydration problem and the background CSS is not applied properly.

https://v2.docusaurus.io/feedback/p/api-documentation-swagger

This is because we "redirect" from 404.

function NotFound({location}) {
  if (/^\/feedback/.test(location.pathname)) {
    return <Feedback />;
  }
  return <div>404</div>;
}

The problem is that the server-side rendering is the 404 page, and the first client render is the feedback page. It creates a mismatch between the static page and the first react render (see https://joshwcomeau.com/react/the-perils-of-rehydration)

Not sure exactly how to fix this easily in a portable way.

In Gatsby there's the client only routes concept: https://www.gatsbyjs.org/docs/client-only-routes-and-user-authentication/