Sadly this is has been a bug that is still a problem and recently escalated a full year later. Not sure how many others have encountered this bug, but we recently upgraded our portal from 10.7.1 to 10.9.1,that hosts secure services we consume using AGO web applications and the problem is also in the latest portal, which makes sense since I've been told its an AGO bug, even though at first service call a year ago, we were told to upgrade our portal.