SSL cert not working on pages hosted on gitlab.io

I’m hosting the documentation for one of my projects using GitLab pages on gitlab.io
It has TLS enabled but the browser gives a warning about the certificate.
I assume this is because my gitlab.com username has a dot and the *.gitlab.io cert doesn’t match the domain for my user (mattia.basaglia.gitlab.io)
(The pages site for the project in question is https://mattia.basaglia.gitlab.io/tgs/)

Seems like a bug with how gitlab.io certs are set up, but I’m not sure where is the best place to report this so I’m asking here.

I have the same issue. Have you found a solution?