&gt; &quot; When you take an app that&#x27;s been worked on for 15 or so years and then replace it&#x27;s UI you&#x27;re going to lose a TON of features. &quot;<p>What makes you think they&#x27;ll drop XUL as soon as the first release of the HTML-based UI? It&#x27;s pretty obvious they&#x27;d want to support both until the HTML UI was close to feature complete. You&#x27;re finding problems where there aren&#x27;t any.