Don't suggest outdated MQTT client without MQTT 5 support.

[reitermarkus]

Using MQTT Explorer to publish /command/save doesn't work since an MQTT 5 response topic needs to be specified, otherwise the command handler isn't actually executed. Suggest using MQTTX instead, which supports MQTT 5, including setting the response topic.

MQ3T seems to be a more similar replacement with MQTT 5 support, but doesn't yet have a way for setting the response topic.

[jordens]

I agree that mqtt-explorer is not a good tool for many jobs. See also quartiq/stabilizer#961
Note that mqtt-explorer is only suggested for viewing telemetry and settings, not for setting then and not for executing commands.
Every generic mqtt explorer tool will become insufficient very quickly when used for this. That's inherent to the approach. They are not meant to be used regularly for anything, only as a debugging tool. If you do, you are doing it wrong.
Rather than finding the "best" mqtt explorer (that sucks the least), I'd help people setting up telemetry scraping and their own tooling using miniconf.

And your PR falls short of addressing the actual issue you face, document using save with some mqtt explorer thing.

[jordens]

And there is no need to suggest a mqtt5 explorer precisely because in the use cases envisioned and mentioned the mqtt5 features are not needed.

[reitermarkus]

Added an example for command/save. Let me know if I should change the telemetry example to use MQ3T instead to also provide graphs.

[jordens]

Given that I can't see a tool that covers both the important task of telemetry browsing with plotting and the MQTT5/response-topic stuff, I don't see the improvement of the PR.
I'm fine with listing multiple external tools (along with their limitations/advantages). Then also include mqttui. But a tutorial on how to use them won't fly here.

[jordens]

Certainly not. MQTTX doesn't do any plotting. It's strictly worse than MQTT-Explorer for those tasks!