Uport attestation push bug

bug_demo.js

/**
  This file to be used in the tutorials folder of uport-js repo
  
  Replace PUBLIC_URL with your machine's publicly accessible URL
  Run using `node bug_demo.js`
  
  Expected behaviour: The uPort mobile app should show first show a dialog for login then 
                      a dialog displaying an attestation received
  
  Actual behaviour: The uPort mobbile app shows an empty white dialog after the login dialog.
*/

var express = require("express");
var uport = require("../lib/index.js");
var jsontokens = require("jsontokens");
var bodyParser = require("body-parser");
var mnid = require("mnid");

var PUBLIC_URL = "https://d15d9c72.ngrok.io/callback";

var signer = uport.SimpleSigner(
  "8508376b07cac93ad4871cea6b3d455b58e4ef44d00b6f2cc1338620bbb2a307"
);

var credentials = new uport.Credentials({
  appName: "Bug Demo",
  address: "2ous7nUuzrJ77Q7U2ngtCsLWpyFPQKtP6Ch",
  signer: signer,
  networks: {
    "0x3": {
      registry: "0x41566e3a081f5032bdcad470adb797635ddfe1f0",
      rpcUrl: "https://ropsten.infura.io"
    }
  }
});

var app = express();

app.use(bodyParser.json({ type: "*/*" }));

app.get("/", function(req, res) {
  credentials
    .createRequest({
      network_id: "0x3",
      notifications: true,
      callbackUrl: PUBLIC_URL,
    })
    .then(function(requestToken) {
      var uri =
        "me.uport:me?requestToken=" + requestToken + "%26callback_type=post";
      var qrurl =
        "http://chart.apis.google.com/chart?cht=qr&chs=400x400&chl=" + uri;
      var mobileUrl =
        "https://id.uport.me/me?requestToken=" +
        requestToken +
        "&callback_type=post";
      console.log(uri);
      res.send(
        "<div><img src=" +
          qrurl +
          "></img></div><div><a href=" +
          mobileUrl +
          ">Click here if on mobile</a></div>"
      );
    });
});

app.post("/callback", function(req, res) {
  var jwt = req.body.access_token;
  console.log(jwt);
  var ethAddress;
  var pushToken;
  var user;
  credentials
    .receive(jwt)
    .then(function(creds) {
      console.log("creds", creds);
      if (creds.address) {
        user = creds;
        console.log("uPort profile retrieved");
      } else {
        console.log("Verification failed.");
      }
    })
    .then(() => {
      return credentials.attest({
          sub: credentials.address,
          claim: {
            "CREDS": "TRUE"
          }
        });
    })
    .then(att => {
      console.log("attesting", att, user.pushToken)
      return credentials.push(user.pushToken, user.publicEncKey, {url: `me.uport:add?attestation=${att}`, message: "wat"})
      console.log(jsontokens.decodeToken(att))
    })
    .then(console.log)
    .catch(console.log);
});

var server = app.listen(8081, function() {
  console.log("Tutorial app running...");
});