Github pages sends a 301 for resources without a trailing slash, which rewrites HTTPS -> HTTP.
<div id="main">
<a href="/"><h1 id="title">i3 - improved tiling WM</h1></a>
<ul id="nav">
-{% include menulink.html name="Docs" url="/docs" %}
-{% include menulink.html name="Screens" url="/screenshots" %}
+{% include menulink.html name="Docs" url="/docs/" %}
+{% include menulink.html name="Screens" url="/screenshots/" %}
{% include menulink.html name="FAQ" url="https://www.reddit.com/r/i3wm/" %}
-{% include menulink.html name="Contact" url="/contact" %}
+{% include menulink.html name="Contact" url="/contact/" %}
{% include menulink.html name="Bugs" url="https://github.com/i3/i3/issues" %}
</ul>
<br style="clear: both">