Hi-
This was just a manual copy/reindex from our Kibana 5.X index that keeps failing to migrate. So now whenever we have to restart Kibana we'll manually remove the ".kibana_x" indexes, remove the alias from .kibana and then start fresh. Kibana creates a .kibana_1 and .kibana aliases to it and then we just change the alias again "kibana_8" that keeps failing migration but works if we change the alias while it's running.
Settings are default I think because its commented out:
# Kibana uses an index in Elasticsearch to store saved searches, visualizations and
# dashboards. Kibana creates a new index if the index doesn’t already exist.
#kibana.index: ".kibana"