Sync your Github account with Utopian Bug Report

Today I want to report a bug Sync your Github account with Utopian Chrome Extensions
Repo
https://github.com/utopian-io/utopian-extension

When we want to Use Sync Github botton we will forwarding for autorise below info and if we can accept it we have ERRR_CONNECTION_REFUSED then the page goes blank

https://github.com/login/oauth/authorize?client_id=1ed58da028b638550c03&redirect_uri=http://localhost:3000/github/callback&scope=repo,user,gist&state=http://localhost:3000/github/callback?code=0f5e4828e1dea0e996aa&state=https%3A%2F%2Fgithub.com%2F

http://localhost:3000/github/callback?code=0f5e4828e1dea0e996aa&state=https%3A%2F%2Fgithub.com%2F

here is coding problem if the owner want to make a correction : githubCallback section

var endpoint = 'http://localhost:4040/api';
var steemConnectCallback = 'http://localhost:3000/callback';
//var githubClient = '06b0ef5509fc7de00493';
//var githubCallback = 'https://utopian.io/github/callback';

var githubClient = '1ed58da028b638550c03';
var githubCallback = 'http://localhost:3000/github/callback';

function getCurrentTabUrl(callback) {
// Query filter to be passed to chrome.tabs.query - see
// https://developer.chrome.com/extensions/tabs#method-query
var queryInfo = {
active: true,
currentWindow: true
};`
https://github.com/utopian-io/utopian-extension/blob/master/utopian.js

Offical Chrome 62.0.3202.94 64bit
Windows 10 Pro