una/template/menu_custom_item.html

<span class="bx-def-margin-right bx-def-margin-thd-topbottom">
    <a href="__link__" target="__target__" onclick="__onclick__" title="__title_attr__">
        <bx_if:icon><i class="sys-icon __icon__"></i></bx_if:icon>
        <bx_if:image><img style="background-image:url(__icon_url__)" src="<bx_icon_url:spacer.gif />" /></bx_if:image>
    </a>
    <bx_if:addon>__addon__</bx_if:addon>
</span>