If one enables giscus for comments it will fail, since it needs the lang: "X" tag, this is currently not in the docs and should be added to avoid confusion and time wasting.

Second is a feature that giscus supports but Hextra does not use and its Lazy loading, it should be implemented to improve the performance of page loading

I found this article that goes into details, and it seems easy to implement

https://www.bloovis.com/posts/2026-08-26-giscus-hugo-hextra/