icingaweb2/modules/monitoring/application/views/scripts/chart/hostgroup.phtml

<?php if (! $this->compact) { ?>
    <div class="svg-container-responsive">
        <?= $chart->render(); ?>
        <?= isset($chart2) ? $chart2->render() : ''; ?>
    </div>
<?php } else { ?>
    <?= $chart->render(); ?>
<?php } ?>