Publishing to MQTT appears to be unavailable

I have Emoncms 11.0.5 on a small PC running Ubuntu 20.04. Mosquitto MQTT broker is installed on the same PC and working successfully. I want to publish a feed to MQTT for use by another application but I can’t see how to do it. I’ve read the brief instructions at MQTT - Guide | OpenEnergyMonitor. On the feeds page I can set up a process for a virtual feed but the Publish to MQTT option isn’t available in the list. The wrench icon, which links to the process config, isn’t shown for a real feed. By debugging the feed processor user interface I can see the Publish to MQTT option is there but disabled for a virtual feed. I can publish to a feed from elsewhere so I know Emoncms can connect to the broker.

Should I be able to set up a process list for a real feed?
Why isn’t Publish to MQTT available for a virtual feed?
Is there something I need to do to enable publishing to MQTT?

You publish to MQTT as part of the input processing, not from the Feed. i.e. when you add a value to a Feed (log to feed or store the value) you also publish that same value to MQTT.

Do not use emon as the outgoing base topic.

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Thanks. It was hiding in plain sight. Perhaps I missed it because on the feeds page the icons are all at the top, but on the inputs page the icon I needed is over to the right of the input.

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