听说 GitHub Pages 对自定义域名支持 HTTPS 有段时间了，尝试过把那个放在 GitHub Pages 上长草的 Jekyll 垃圾站启用 HTTPS，无奈尝试几次无果。域名换过，CNAME 删除了重新添加过……还是无法 Enforce HTTPS.
今天试着用 A 记录方式解析到 GitHub IP，没几分钟，刷新一下状态，看样子有戏。
A 记录 IP
18.104.22.168 22.214.171.124 126.96.36.199 188.8.131.52
via：GitHub - Setting up an apex domain
如无意外，我的垃圾 Jekyll 站明天就能启用 HTTPS。
Today, custom domains on GitHub Pages are gaining support for HTTPS.
Secure connection to ben.balter.com
GitHub Pages is the best way to quickly publish beautiful websites for you and your projects. Just edit, push, and your changes are live. GitHub Pages has supported custom domains since 2009, and sites on the *.github.io domain have supported HTTPS since 2016. Today, custom domains on GitHub Pages are gaining support for HTTPS as well, meaning over a million GitHub Pages sites will be served over HTTPS.
HTTPS (most recognizable as the lock icon in your browser’s address bar) encrypts traffic between GitHub’s servers and your browser giving you confidence that the page you asked for is the page you’re reading, from the site you think it is, and that others can’t snoop on or modify its contents along the way.
We have partnered with the certificate authority Let’s Encrypt on this project. As supporters of Let’s Encrypt’s mission to make the web more secure for everyone, we’ve officially become Silver-level sponsors of the initiative.
Action may be required on your part to secure your custom domain.
If you are using CNAME or ALIAS records for your custom domain, you’re all set and your site should be accessible over HTTPS. If it is, and your site loads correctly over HTTPS, you can optionally enforce HTTPS in your repository’s settings. Users who request your site over HTTP will be upgraded to HTTPS.
If you are using A records, you must update your site’s DNS records with new IP addresses. Please see our guide to setting up your custom domain with Pages and update any A records you might have set.
Once your updated DNS records have propagated, and you’ve confirmed that your site loads correctly over HTTPS, you can optionally “Enforce HTTPS” for your domain in your repository’s settings, ensuring users who request your site over HTTP are upgraded to HTTPS.
These new IP addresses don’t just allow us to serve your site over HTTPS, but also places your site behind a content delivery network (CDN), allowing us to serve your site from data centers around the world at fast speeds, and offering additional protection against DDoS attacks. While the previous IP addresses will remain available for a transition period, we recommend you migrate to the new IP addresses to gain these benefits.
2018.5.30 18:04，24小时过去了，Enforce HTTPS 还是没能勾上。状态仍然没变：
Not yet available for your site because the certificate has not finished being issued. Please allow 24 hours for this process to complete. (jekyll.cyhour.com)
2018.5.31 8:30，状态还是没改变。不死心，在这发了个信息：Drop us a line，那个状态和自定义域名一起复制过去，然后大意说已经过去 24 小时了，还是没生效。
没多久，Enforce HTTPS 能勾上了。