Failed to establish local tunnel in Jira Activity Tutorial

I am having this exact same problem right now. Just following the tutorial, I get this “Failed to establish local tunnel” error constantly… and then suddenly I don’t?.. and then it comes back again with literally no code change.

I’ve turned it on and off again, to no avail.
I’ve done the tutorial last week without any issues. It just started today, doing the tutorial again from scratch.

This is a MBP running Mojave. I’m not running Apache or any other services.
Usually it manifests as

Failed to establish local tunnel
err = Error: [object Object]

but sometimes it is

Failed to establish local tunnel
err = Error: connect ECONNREFUSED 127.0.0.1:4041
Error: connect ECONNREFUSED 127.0.0.1:4041
Error: connect ECONNREFUSED 127.0.0.1:4041
    at TCPConnectWrap.afterConnect [as oncomplete] (net.js:1106:14)

and for a short time I added some logging lines to register-jira-conf.js and the problem went away? Then I removed the logging lines and the problem reappeared. I added back the logging lines and… problem persisted? So I don’t know what’s happening here.