Some XUL Widgets
menus: menubar, menupopup, menuitem,
menuseparator
toolbars: toolbar, toolbaritem, toolbox (holds
toolbars and adds grippies for collapsing)
titledbutton, progressmeter, tri-state
checkbox
tree: tree, treecaption, treecolgroup, treecol,
treehead, treechildren, treeitem, treefoot,
treerow, treecell
tab view: tabcontrol, tabbox, tab, tabpanel,
titledbutton