OSearched for it some further time and looked for that serial bug on github. I got three versions active
openhab> list -s |grep serial
212 ā Active ā 80 ā 3.14.0 ā com.neuronrobotics.nrjavaserial
213 ā Active ā 80 ā 3.15.0.OH2 ā com.neuronrobotics.nrjavaserial
246 ā Active ā 80 ā 2.5.0.201904260323 ā org.openhab.core.config.serial