Multiple widgets in a html page doesn't work

```html
<script src="/js/widget.js"   
        data-schema="schema1.json">
</script>  
<script src="/js/widget.js"
        data-schema="schema2.json">      
</script>                                             
```

Fails with:

```
Uncaught Error: only one instance of babel-polyfill is allowed
```