GitHub just added HTTPS to github.io pages

Posted Jun 9, 2016 2:30 UTC (Thu) by david.a.wheeler (subscriber, #72896)
Parent article: Core Infrastructure Initiative best-practices badge

Good news... as of today, GitHub Pages now officially supports HTTPS for all <username>.github.io sites, because they now encrypt the CDN/github link. They still don't support HTTPS on custom domains, but this is still a big improvement. Details here:

https://github.com/blog/2186-https-for-github-pages