Resteasy-CDI tries to create beans for every JAX-RS resource and provider, involving creation of proxy classes. This is not possible for org.camunda.bpm.engine.rest.mapper.MultipartPayloadProvider because it is final. Since resteasy-cdi is an implicit module dependency for JAX-RS deployments on JBoss/Wildfly, running into the resulting exception because of this may not be a nice experience for unexperienced users.
Remove final qualifier from class
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