Cannot subscribe to topics with ProtoBuf payloads

[NomadQA]

I cannot subscribe to topics with ProtoBuf payloads as both the _on_message and _on_message_list callbacks within MQTTKeywords.py return the payload decoded to utf-8, with the .decode('utf-8'). With ProtoBuf messages, since they are simply raw bytes which are able to contain bytes that cannot be decoded to utf-8, the decode fails and an error message like the following is received: UnicodeDecodeError: 'utf-8' codec can't decode byte 0x97 in position 63: invalid start byte

Is there any plans to allow ProtoBuf payloads?