There might be AJAX content loading afterward that is not encrypted. That's why it may pass that online test. It probably doesn't run the page's scripts.
As mentioned - Blue host resolved my issue - but I throught it was interesting as this site(not forum) suffered from the same problem with the new FF update. I dont know if there further changes to teksyndicates site recently or whether new FF update as eradicated the problem.
Note that it was only happening on FF, chrome and others are fine.
Not even able to log in through Chrome at the moment due to the unsafe scripts not being loaded and thus the log in handshake not properly coming through.
I see that this a little old, but I noticed the warning in Chrome today about unsafe scripts on the main site and the forums. I was able to log in and the warning went away after logging in, but the fact stands that there still seems to be a problem. (Which is why I clicked this thread when I saw it)
Sorry for the delay in replying - my issue was due to an old version of the security cert being cached in the browser and needing to delete the cert cache. I think it may of also been that the cert hadn't been setup correctly on blue hosts end.