“Session expired. Please log in again” when logging in from Mac

Every time I try to login to internet advancement from my Mac with Firefox I get the error:
“Session expired. Please log in again”

This was previously reported:
Here - ("Session expired. Please log in again" when logging in)
and Here Error: The Session Expired. Please login again

Nothing has changed.

I often see the same behavior. Hold the shift key and click the browser refresh. This often fixes the problem for me.