1. default-consumer-window-size only applies to core clients and it doesn't work or apply for Openwire clients. 

2. There is no way to set the prefetch limit at the broker address or queue level for an OpenWire consumer.

The problem is that when there are many openwire clients and all of them are using XA transactions, it is impossible to set all clients. This discourage users to migrate from AAMQ6 (ActiveMQ) to AMQ7 (Artemis).