I took a look at this thread:
http://www.fordforums.com.au/showthread.php?t=11483277
It appears to be the same issue however reinstalling firefox doesn't resolve this issue. Apparently reinstalling Firefox doesn't clear cookies. hah.
But clicking on the padlock icon and then going down to "Clear cookies and site data" does resolve the issue once I force the browser to go to https://
Why the Edge browser still has the same issue I'll never know.
Problem solved. Thanks russelw!