With the release of Elastic 7.12, Kibana's Discover feature now uses the fields API by default instead of reading from the _source, although the latter is still accessible via Advanced Settings. This change, building on updates in Elasticsearch 7.11, leverages the fields parameter to enhance data retrieval by utilizing both a document’s raw source and index mappings. The fields API offers benefits like handling multifields, field aliases, and consistent formatting of field values, thus simplifying complexities associated with _source and other data handling nuances. The introduction of runtime fields is one of the significant changes, allowing them to be treated like any other field type in Discover. Additionally, object and nested fields display differently, with improvements in handling multi-fields and leaf fields to provide clearer and more structured data presentation. These enhancements streamline the process of field retrieval, reduce confusion caused by discrepancies between ingested and mapped values, and allow for more flexible data handling without requiring deep expertise in Elasticsearch's underlying mechanisms.