Hello,
First off thank you for the 5.4 release!
Was the grok filter downgrade intentional or is this a bug? The documentation also reflects the lower version grok plugin in 5.4.
https://www.elastic.co/guide/en/logstash/current/plugins-filters-grok.html
https://www.elastic.co/guide/en/logstash/5.3/plugins-filters-grok.html
This breaks the use of pattern_definitions in 5.4.
Thanks,
Jeff