@borjasalguero are you kidding me? How about this:

MessageManager.init() will initialize the following:

```js
    document.addEventListener('mozvisibilitychange',
                              this.onVisibilityChange.bind(this));
```

This happens BEFORE ThreadListUI.init()

And inside "onVisibilityChange" there is a call to: ThreadListUI.updateContactsInfo();

It's possible that this is the cause, but it's hard to say since the logic flow is such a mess.