Simple flow to blink, Pin 13 not connecting

I installed the Arduino nodes: https://flows.nodered.org/node/node-red-node-arduino

I imported the flow. The example SimpleDigitalFirmata sketch was uploaded to the Arduino Uno (even though I want to use an ESP32). And the COM3 (which the Uno is connected to) was set in "Edit arduino out node." (Also, the pencil icon was clicked and searched for COM3 and selected.)

Now it just stays on "connecting."

Am I missing something? Thoughts?

Did you load the Firmata firmware?

Usage

The Firmata firmware must be loaded into the Arduino.

See the main documentation for details and examples of how to use this node.

What do you mean? I installed the Arduino nodes in the Palette: node-red-node-arduino.

It works now. I disconnected Node-RED, re-uploaded the program to the Arduino Uno and re-ran Node-RED.

Now I'm looking into how to do the same with the ESP32 (instead of Uno).