In step 8 of "Running the Quickstart" section of the Readme:
After stopping server operating as the singleton master, this server gets an error:

ERROR [org.jboss.as.clustering.jgroups.protocol.NAKACK2] (thread-19) JGRP000039: node1: failed to deliver OOB message [dst: <null>, src: node2 (3 headers), size=73 bytes, flags=OOB|DONT_BUNDLE]: java.lang.IllegalStateException: channel is not connected

The bug which causes this issue is not going to be fixed in 7.1 [1], therefore we should at least document it in the readme.

[1] https://issues.jboss.org/browse/JBEAP-9408?focusedCommentId=13436358&page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel#comment-13436358