Lots of empty fields in expanded document view

This behavior seems fairly new with a recent kibana or other update - when looking at the expanded document for an item in the discover list I see lots of empty fields.

any idea what is causing this and how to remove them?

Apparently these are “date_time” fields that kibana adds to the “docvalue_fields” parameter to queries:

  "docvalue_fields": [
    {
      "field": "@timestamp",
      "format": "date_time"
    },
    {
      "field": "aws.cloudtrail.user_identity.session_context.creation_date",
      "format": "date_time"
    },
    {
      "field": "azure.auditlogs.properties.activity_datetime",
      "format": "date_time"
    },

There is some discussion of this here: https://discuss.elastic.co/t/kibana-using-docvalue-fields-for-no-apparent-reason/236333

But I’m not sure why these fields are being displayed in the results. I’m also not sure if this is a problem upstream or only with the opendistro version.