better use something like:
```javascript
var index = sender.indexOf(' ');
if (index !== -1) {
  sender = sender.slice(0, index);
}
```

`split` makes a lot more work that we don't need :)

As a side note I don't know if taking the first word is what we'd want here, or if taking the contact firstName (if existing of course) would not be better. Lets keep it like this now and we'll refine in a follow-up if necessary.