Does Thingspeak MQTT broker allow retain?

I've been trying to get messages retained using the mqtt3.thingspeak.com broker but they will not retain, either on an Arduino device with pubsub client library, or the MQTTX desktop client. Does the thingspeak broker support the retain flag?

I am correctly (as far as I know) setting the retain flag to true however thingspeak will not deliver a retained message to a client upon connection.

Answer 1

[Christopher Stapels]

The publish channel page says you need to set retain to 0. I think that means retain is not supported, Im sorry.