Github user tzulitai commented on the issue: https://github.com/apache/flink/pull/3750 @fanyon yes that's the general idea. The problem is that if we just replace the old `getSerializableListState` with new access state methods, the new serializer and old serializer (which just uses plain Java object serialization) will be incompatible. So, we actually need to have a new registered state that is migrated from the old one. However, we're planning to have the functionality to convert state serialization formats in Flink 1.4, so now I'm actually not entirely sure if we want to do this "workaround migration with 2 registered states" solution now. Please let me get back to you on this after I think about it ..
--- If your project is set up for it, you can reply to this email and have your reply appear on GitHub as well. If your project does not have this feature enabled and wishes so, or if the feature is enabled but not working, please contact infrastructure at infrastruct...@apache.org or file a JIRA ticket with INFRA. ---