HIVE-20679 a new message encoder was added to Hive that gzips and based64 encodes notification messages. In HIVE-21307 the default encoder was changed to use the gzip encoder, GzipJSONMessageEncoder.
Though Hive 4 is not released, failures as a result of this new message format were reported in
IMPALA-8751. We should add support for the gzip format to prevent future HMS sync issues.