Joe: It is Nifi 1.23.2. The error happens when using JoltTransformJSON on a flowfile with a string field of >20 mb. The message is output as an error to nifi-app.log and the bulletin. In this case base64 content is being produced and added as a json field.
Here is further context: https://github.com/FasterXML/jackson-core/issues/1014 Greg
