Not sure if I need to mention the brilliant firmware for Sonoff/Wemos D1 mini devices, the arendst/TASMOTA.
Currently due to the small memory footprint the CLIENT ID, MQTT Username and MQTT password are limited to 33 chars. Unfortunately, it would appear that your generated keys are longer than that. Is there any possibility to shorten these by standard, or give the user the option to have shorter keys, in exchange for “lesser” security. T hequestion begs, do we really need to go that long? Did I read somewhere that the max length should be 23 bytes at any rate?
I think it would be well worth considering to bring this firmware and devices onboard due to their nearly off-the-shelf readiness and user friendliness.