The primary goal of this version is to prepare for Atlassian's upcoming GDPR changes (currently scheduled for April 29, 2019). While it contains major changes, it should be fully compatible with all your existing workflows. If you identify what you believe is a regression, please report it to us as soon as possible through our Help Desk.
The upcoming GDPR changes will require that you update your workflows or they will eventually stop working. See Spring 2019 breaking changes for GDPR for details.
This version of JMWE for Jira Cloud allows you to start updating your workflow today in preparation for Atlassian's breaking changes.
For a list of other changes, see the full release notes.