<data priority="50">
    <xpath expr="//span[@t-field='o.name']" position="replace">
        <t t-if="', '.join([str(x) for x in o.invoice_line_ids.sale_line_ids.order_id.mapped('x_title') if x])">
            <span> - </span>
            <span t-esc="', '.join([str(x) for x in o.invoice_line_ids.sale_line_ids.order_id.mapped('x_title') if x])"/>
            <br/>
            <span t-field="o.name" style="font-size: 10pt;">RE</span>
        </t>
    </xpath>
</data>