Internal links/anchors on spec.filecoin.io don't open

While reading through the specs on the recommended docs site, I was unable to follow any of the hyperlinks.

Opening e.g. https://spec.filecoin.io/systems/filecoin_blockchain and clicking 'virtual machine' changes the URL to https://spec.filecoin.io/systems/filecoin_blockchain/#section-systems.filecoin_vm, but the view does not change.

I had a try few most of the pages and external links work fine but not internal.

I tried on both firefox and safari to no avail

Reproduce the failure at https://spec.filecoin.io/systems/filecoin_blockchain by clicking “virtual machine,” then compare the resulting anchor URL with the unchanged view in Firefox or Safari. Trace how the documentation site handles the #section-systems.filecoin_vm anchor; done means internal links navigate to the selected section while external links continue to work.

Written by the indexing model from the issue text.