top-level navigation to any sub-path (not the root) will break the side-navigation interactivity

[cody-dot-js]

Description

If you go to https://ngrok.com/docs, the side nav can be opened/collapsed and appears to do client-side navigation

However, if you top-level navigate to or hard-refresh on a sub route (e.g. https://ngrok.com/docs/http/), then the side nav no longer allows you to expand/collapse navigation sections and it appears to kick back over to server-side navigation.