The highlight of this release is the new YAML-based indexer configuration support: indexer configurations can now be defined directly in .yaml files inside the Configuration/KeSearch/IndexerConfigurations/ folder of any extension, in addition to the existing database records. This makes it possible to version-control your search configuration and roll it out automatically during deployment, without any manual steps in the TYPO3 backend.
Full details are available in the ChangeLog and in the new documentation chapter on YAML indexer configuration.