Oauth2 timeout waiting for callback #40

I've setup my app like this:

xurl auth apps add myApp --client-id <client_id> --client-secret <client_secret>

I made sure that the callback URI is set to http://localhost:8080/callback, and I also set some other fields in the X Developers portal (I don't know if that's relevant).
Also note that I'm running xurl on a VPS, if that helps.

This is my ~/.xurl:

apps:
    default:
        client_id: <client_id>
        client_secret: <client_secret>
    myApp:
        client_id: <client_id>
        client_secret: <client_secret>

default_app: myApp

And I'm getting this error when running xurl auth oauth2:

Error in OAuth listener: Auth Error: Timeout (cause: timeout waiting for callback)
OAuth2 authentication failed: Auth Error: Timeout (cause: authentication timed out)