&gt;I&#x27;m not sure what you&#x27;re actually comparing this workflow to.<p>He is comparing it to what they have now, XUL + CSS + JavaScript. Replacing it with html isn&#x27;t as big a change as it sounds, their UI is already written in XML and rendered by Gecko, all they are doing is moving from a custom XML like XAML(MS) or FXML(Java) to standard HTML rendered by Gecko.