Many people here recognize something similar to the Google Chrome warning: "This page includes script from unauthenticated sources."
If you look at the code behind the website, you see there are many references to specific protocols, such as
https. For example:
This should be replaced by a protocol relative URL:
In that case people can happily proceed
Note that this is not just Chrome, also in Internet Explorer. You will recognize it happening to you, if you suddenly get a popup to fill in a CAPTCHA. Or if you create a question and you don't see the buttons on top and the preview below your post.