I found some related issues:
But I also believe it's a new bug. My bad luck is that this bug hampers the workaround for another bug described here.
I was testing with AS 7.1 on my local machine, but my organization has JBoss EAP on all server machines.
I installed EAP 6.0 locally and observed the exact same problem.
What is the github URL for the latest AS 7.2.x upstream?