Yep, and most of the UI in Firefox is either XUL or HTML, both of whom are rendered by Gecko. This is not the case on Android, for technical reasons (libxul is

Yep, and most of the UI in Firefox is either XUL or HTML, both of whom are rendered by Gecko. This is not the case on Android, for technical reasons (libxul is too long to load, so we rely on Java, which is pre-loaded by the OS, to display the UI).