Why am I suddenly getting a “Blocked loading mixed active content” issue in Firefox?

Question

This morning, upon upgrading my Firefox browser to the latest version (from 22 to 23), some of the key aspects of my back office (website) stopped working.

Looking a

Answer 1

In the relevant page which makes a mixed content https to http call which is not accessible we can add the following entry in the relevant and get rid of the mixed content error.