We should provide "limitation" notes for colocated HA topology in chapter 4.4.6. Colocated Backup Servers.

http-acceptors/http-connectors can be used to create colocated HA topology only if different http listeners are used for master and slave connectors. Use of remote-acceptors/remote-connectors is recommended.

[1] https://access.stage.redhat.com/documentation/en/red-hat-jboss-enterprise-application-platform/version-7.0/configuring-messaging/#colocated_backup_servers