Redoc demo page - side tab focused not on correct place

[WilsonZheng]

On the demo page (https://rebilly.github.io/ReDoc/), when clicking on tab "Logs user into the system" or
"Logs out current logged in user session", the tab highlight will still focus on "Creates list of users with given input array". The following are the screenshots of the issues:

In my own project, I got a similar problem when clicking on the last tab in the sidebar. the tab highlight will always point to the previous one.