When a wiki is set to use HTTPS / SSL, the image for RSS Feeds at the bottom of the forum page is loaded over HTTP.
<span class="rss-icon">
<img src="http://www.wikidot.com/common--theme/base/images/feed/feed-icon-14x14.png" alt="rss icon">
</span>
This is the icon I am referring to:
A wish exists that asks for similar functionality on the ListPages module, but this is a bug because it's an RSS feed generated by a core part of the wiki (forum system) and cannot be changed to make it compliant even manually.
Related wish: Option to specify HTTPS for RSS feeds