The Java Execution Engine has been the default engine since Logstash 7.0, and works with plugins written in either Ruby or Java. Removal of the Ruby Execution Engine will not affect the ability to run existing pipelines. #12517
We have added support for UTF-16 and other multi-byte-character when reading log files. #9702
The Field Reference parser interprets references to fields in your pipelines and plugins. It was configurable in 7.x, with the default set to strict to reject inputs that are ambiguous or illegal. Configurability is removed in 8.0. Now Logstash rejects ambiguous and illegal inputs as standard behavior. #12466
Option to pass custom data to the benchmark CLI
We have added another flag to the Benchmark CLI to allow passing a data file with previously captured data to the custom test case. This feature allows users to run the Benchmark CLI in a custom test case with a custom config and a custom dataset. #12437