PUBLIC MARKS with tags user & xul

When editing userChrome.css, you must add CSS selectors based on the element names and IDs/classes of the XUL user interface. There is no comprehensive listing of every single possible selector to use when styling the user interface (just as it would be silly to create such a comprehensive list for a web page), but a few of the more common and interesting selectors are listed below. The best way to discover how to select an element in the user interface is to use the DOM Inspector.

The XML User Interface Language (XUL) is a markup language for describing user interfaces. With XUL you can create rich, sophisticated cross-platform web applications easily.