Incompatibility while using co.elastic.apm:apm-opentracing:1.6.1 and elastic-apm-agent-1.6.1

We have an issue for that here: https://github.com/elastic/apm-agent-java/issues/634

But note that OpenTracing is discontinued and will live on as OpenTelemetry with a completely different api. I still think it makes sense that the Java agent will have support for the final version though. But there are a lot of backwards incompatible changes which makes supporting multiple versions really difficult. While I'd like to tackle this and find solutions right away, it's difficult to prioritize this over other features ATM.