JSFiddle - React, Tailwind, and code Playground

HTML

<script src="http://cdn.firebase.com/v0/firebase.js"></script>

JavaScript

var rootRef
rootRef = new Firebase("https://MeowImACat.firebaseio-demo.com");
rootRef.remove();

// No Error
rootRef.child('catfood').setWithPriority("Hello", Number.NEGATIVE_INFINITY);


// Error: Uncaught Error: Attempted to find predecessor key for a nonexistent key.  What gives?
rootRef.once("child_added", function (snapshot, prevChildName) {});
rootRef.child('catfood').setWithPriority("Hello", Number.NEGATIVE_INFINITY);