ElasticSearch 7.12.0 responds with "Content-Type header [] is not supported"

[obi-jon]

There appears to be a requirement from elasticsearch 7.12.0 to have a content-type header.

The configuration used here is the docker image for elasticsearch and kibana 7.12.0 in a network, a separate container running DVWA and burp pro on the local host pointed at elasticsearch.

The post from elastic burp does not include a Content-Type header

The response from elasticsearch gives the impression that the Content-Type header is necessary

A text file following the HTTP thread. The data is from a burp scan of DVWA (no sensitive date)
elasticBurp.txt

Docker command used to run DVWA
docker run --name=dvwa -d vulnerables/web-dvwa

Docker-Compose Yaml file for ElasticSearch and Kibana
docker-compose.yml.txt