Today I made a stupid mistake. I am using TypeKit and I added my reference like so:
<script type="text/javascript" src="http://use.typekit.com/….js"></script>
Can you see what’s wrong?
It works great in local development, however when I deploy to production, I will be using HTTPS. When my page tries to hit the TypeKit servers over HTTP, my browser is going to complain about insecure connections.
I could switch to
<script type="text/javascript" src="https://use.typekit.com/….js"></script>
but instead I decided to make my link protocol relative:
<script type="text/javascript" src="//use.typekit.com/….js"></script
this way it will call the protocol that my site is currently serving. TypeKit does support HTTPS.