GitLab default url not secure

Question

I'm trying to set up a Gitlab Page to host my personal site (CV, code examples that sort of thing) with the standard userName.gitlab.io domain.
At the moment it's just a HelloWorld in index.html and readme.md I pushed to check it's all working, (and it is).

The problem is when I access the site through https on Firefox I get :

This site uses HTTP Strict Transport Security (HSTS).

The advanced message

mr.brompton.gitlab.io uses an invalid security certificate. The certificate is only valid for the following names: *.gitlab.io, gitlab.io Error code: SSL_ERROR_BAD_CERT_DOMAIN

I can access through Chrome but only with http. All of the documentation I have read suggests https should work automatically. Again I feel I'm missing something stupid. Perhaps I should just add my own cert?

The repo can be found @ mr.brompton.gitlab.io or gitlab.com/mr.brompton

my config yaml:

  # Full project: https://gitlab.com/pages/plain-html
pages:
  stage: deploy
  script:
  - mkdir .public
  - cp -r * .public
  - mv .public public
artifacts:
  paths:
  - public
only:
  - master

Answer 1

The answer was something simple as I suspected. The project was named mr.brompton which meant my domain was mr.brompton.gitlab.io. The certificate is valid for *.gitlab.io. This meant the cert was returning invalid after trying to find gitlab.io after the mr.*. I fixed the problem by changing my user name, project path and project name to mr-brompton. I will also change the url's, username and all other associations on my local machine.