404 error going to core.async rational page

[lkrubner]

If I go here:

https://clojure.org/reference/async

and I click the link for "core.async Rationale" then I go to this URL:

https://clojure.org/about/async

but this gives me a 404 error.

[felixdo]

Also the "Walkthrough" link next to it is dead: https://clojure.org/guides/async-walkthrough