Arduino code base is really lacking any form of MQTT5.0 client libraries, I think this could extremely useful not just to me but too many other people running this software on a host of the latest boards.

I don't quite get how to end the AUTH exchange when using the enhaced authentication feature. I'll explain:

First I send a connect using the connectTo method including the authData and authMethod properties.

If the authMethod is supported by the broker, it sends back and AUTH packet with reason code 24, continue authentication, this triggers the authReceived function back in the client to process the data. So far, so good.

Then, I send the response back to the broker with the auth method, this sends an AUTH packet to the broker with reason code 24 continue authentication and the data needed to end the authentication in the broker.

Lastly, my broker sends back a CONNACK packet with reason code 0 success if the data is correct or 135 not authorized if it's not.

At this point, the auth method fails with an error code 130 Protocol error.

Now, if I'm reading your code correctly, after the auth method sends the AUTH packet, it waits for the response, but only considers the case of the response being another AUTH packet and not a CONNACK one, so it dismiss the packet as a Protocol Error.

Shouldn't the auth method consider the case of the response from the broker being a CONNACK packet or there's something else I'm missing?

Thank you in advance.