- Upgrade core libraries (Kafka 3.0.1, Netty, Hibernate, etc.) – Kafka upgrade enables idempotence by default
- Add new JavaVersion enum constant EIGHTEEN
- Fix a range of bugs (configuration symmetry, Thymeleaf reactive auto‑config, Tomcat keep‑alive, Actuator @ReadOperation, Prometheus allocation, R2DBC metrics, etc.) and improve documentation throughout the reference guide