I am looking at ActiveMQ (Red Hat AMQ Broker in particular) and trying to find out what integrations/connectors are available apart of the supported protocols (JMS, AMQP, MQTT, OpenWire).
For Kafka, there is e.g. the Confluent hub, https://www.confluent.io/hub/. Is there something similar for ActiveMQ?
I am especially interested in reading & writing messages from
Is there any out-of-the-box or existing 3rd party support, or do I need to implement it?
For a statement about things that Red Hat officially supports you should contact Red Hat directly.
I recommend you look at Apache Camel for 3rd party integrations for ActiveMQ brokers. Camel routes can be deployed directly on both ActiveMQ 5.x and ActiveMQ Artemis brokers. Camel can integrate with files, databases, HTTP, HDFS, JMS, AMQP, MQTT, STOMP, and many more (including Kafka).