Validation API got error with highlight.(org.elasticsearch.common.ParsingException: request does not support [highlight]

Hello :slight_smile:

I tried highlight with reference to the following document.

(using docker.elastic.co/elasticsearch/elasticsearch:7.5.1)

This example works fine, but when I check it with the validation api, I get an error.

GET test_index/_validate/query?explain
{
    "valid": false,
    "error": "org.elasticsearch.common.ParsingException: request does not support [highlight]"
}

How do I resolve this error? Can highlight not be validated with the validation API?