we updated our Jenkins from 1.651.3 to 2.60.3 and our Kubernetes plugin from 0.11 to 1.0.
We noticed wiping out home directory content (defined in Dockerfile) of the container slave after spinning it up in the new Jenkins setup. We were able to compare new and old setup (described above) to confirm this issue manifests in the new setup and not in the old one.
This behavior is new and not announced in CHANGELOG . Carlos Sanchez confirmed that this is not expected. This  looks like the same issue (although we used /var/lib/jenkins for home).
Hope this saves some investigation to someone and helps with finding the bug.