"Error: Firebase (2.2.6) INTERNAL ASSERT FAILED: listen() called twice for same path/queryId.
Hc@https://cdn.firebase.com/js/client/2.2.6/firebase.js:35:1651
J@https://cdn.firebase.com/js/client/2.2.6/firebase.js:35:1622
h.xf@https://cdn.firebase.com/js/client/2.2.6/firebase.js:185:287
Kh/this.O<.Xe@https://cdn.firebase.com/js/client/2.2.6/firebase.js:201:344
uf@https://cdn.firebase.com/js/client/2.2.6/firebase.js:118:55
gf.prototype.Ob@https://cdn.firebase.com/js/client/2.2.6/firebase.js:115:34
Vh@https://cdn.firebase.com/js/client/2.2.6/firebase.js:207:301
Y.prototype.Eb@https://cdn.firebase.com/js/client/2.2.6/firebase.js:225:223"