As we mentioned a few weeks ago, CodePen will be going entirely HTTPS on June 1, 2017. That article goes into why and how it might affect for you.
This post is another reminder that it's happening! But, we also want to share some steps we're taking to help the process along.
Non-Secure Resources Now Visually Marked
You'll see this in settings if you're using a non-secure URL:
We're Updating Many Non-Secure URLs Automatically For You
New Pens Now Default to HTTPS
Any new Pen you create will start at an HTTPS URL. That way, as we march toward flipping the switch everywhere, anything you've made recently will very likely be unaffected since it was created over HTTPS to begin with.