<!-- NOTE: only one of the next two columns will be displayed. -->
<td py:if="val"><a href="${zabbix_event_ack_link(node[5])}">Provide Ack</a></td>
<td py:if="not val" py:content="node[5]">Message from user</td>
<!-- NOTE: only one of the next two columns will be displayed. -->
<td py:if="val"><a href="${zabbix_event_ack_link(node[5])}">Provide Ack</a></td>
<td py:if="not val" py:content="node[5]">Message from user</td>