elasticsearch/docs/reference/migration/migrate_6_0/analysis.asciidoc

[[breaking_60_analysis_changes]]
=== Analysis changes

==== Synonym Token Filter

In 6.0, Synonym Token Filter tokenizes synonyms with whatever
tokenizer and token filters appear before it in the chain.

The `tokenizer` and `ignore_case` parameters are deprecated
and will be ignored when used in new indices.  These parameters
will continue to function as before when used in indices
created in 5.x.