Github user tillrohrmann commented on the issue:
https://github.com/apache/flink/pull/5114
It depends a little bit on 1.4. We have serious build stability issues in
the `release-1.3` branch and it would take a serious effort to stabilize it
again. If I could choose, then we wouldn't have to release 1.3.3 because users
switch directly to 1.4.---
