Logout redirect fails

This is the redirect code:
window.location.replace(“https://xxx.eu.auth0.com/v2/logout?returnTo=http%3A%2F%2F"+location.hostname+":40005/console.html”);

this code has worked in the past, so it must be a configuration error, I don’t know what else I can do beyond adding the url to the allowed logouts

Since this allowed logout functionality appears to be insufficiently documented or buggy, is there anyway to disable it?