When accessing pages that use MathJax (example: Subexponential algorithms for DLP in ℤs×ℤt) via the HTTPS protocol, we now use the CDN specified by the MathJax FAQ:
How do I access the MathJax CDN using a https secure connection?
The MathJax CDN utilizes Rackspace’s CDN service. Unfortunately, this currently does not offer https support for the default address cdn.mathjax.org. However, as an alternative, you can use the following unmapped address:
https://c328740.ssl.cf1.rackcdn.com/mathjax/latest/MathJax.js
While not as appealing as cdn.mathjax.org, this address is stable and safe to use. For more information, see our documentation.
So everyone should now be able to enjoy the beauty of quality mathematics notation whichever protocol they prefer.