Some repositories are unkown

[llrs]

The following search works under normal github.com: icon.png repo:clauswilke/clauswilke.github.io language:HTML.
However, when I do that on cs.github.com I get a "unknown repo: "clauswilke/clauswilke.github.io""

The repository is not accessible under: https://cs.github.com/clauswilke/clauswilke.github.io but it is on https://github.com/clauswilke/clauswilke.github.io
If I had to guess probably it is something about the dots on the repo name.
Thanks!