com.github.benmanes.caffeine.jcache.copy.JavaSerializationCopier is still needed;
I see. I'd say the most user friendly solution would be to create a new extension camel-quarkus-jcache-caffeine that would host this reflection registration plus it would depend on quarkus-caffeine. We should also add a hint to extensions/jcache/runtime/src/main/doc/usage.adoc that end users may want to depend on camel-quarkus-jcache-caffeine if they want to use caffeine as a jcache impl.
I submitted a PR to Quarkus https://github.com/quarkusio/quarkus/pull/27937
Once merged, all we need to do is some cleanup in camel-quarkus-jcache, and no need to introduce another extension.
Follows up https://github.com/apache/camel-quarkus/pull/4088
and the discussion in https://github.com/apache/camel-quarkus/issues/1846#issuecomment-1245928494