function debug_toggle(evt, obj)
{
    if (obj.style.height == '') {
        obj.style.height = '1.2em';
        obj.style.overflow = 'hidden';
        obj.style.backgroundColor = 'khaki';
    } else {
        obj.style.height = '';
        obj.style.overflow = '';
        obj.style.backgroundColor = 'lightyellow';
    }
    if (evt.stopPropagation) {
        evt.stopPropagation();
    } else {
        evt.cancelBubble = true;
    }
}