icingaweb2/modules/setup/application/views/scripts/form/setup-requirements.phtml

<?php

use Icinga\Web\Wizard;
use Icinga\Module\Setup\Requirements;

$requirements = $form->getRequirements();

?>
<table class="requirements">
  <tbody>
<?php foreach ($requirements as $requirement): ?>
    <tr>
      <td><h2><?= $requirement->title; ?></h2></td>
      <td style="width: 50%"><?= $requirement->description; ?></td>
      <td class="state <?= $requirement->state === Requirements::STATE_OK ? 'fulfilled' : (
        $requirement->state === Requirements::STATE_OPTIONAL ? 'not-available' : 'missing'
      ); ?>"><?= $requirement->message; ?></td>
    </tr>
<?php endforeach ?>
    <tr>
      <td></td>
      <td></td>
      <td class="btn-update">
        <div class="buttons">
          <a title="<?= $this->translate('You may also need to restart the web-server for the changes to take effect!'); ?>" href="<?= $this->href(); ?>" class="button-like"><?= mt('setup', 'Refresh'); ?></a>
        </div>
      </td>
    </tr>
  </tbody>
</table>
<form id="<?= $form->getName(); ?>" name="<?= $form->getName(); ?>" enctype="<?= $form->getEncType(); ?>" method="<?= $form->getMethod(); ?>" action="<?= $form->getAction(); ?>">
  <?= $form->getElement($form->getTokenElementName()); ?>
  <?= $form->getElement($form->getUidElementName()); ?>
  <div class="buttons" style="margin: 0 0 1.5em;">
    <?= $form->getElement(Wizard::BTN_PREV); ?>
    <?php
      $btn = $form->getElement(Wizard::BTN_NEXT);
      if (false === $requirements->fulfilled()) {
          $btn->setAttrib('disabled', 1);
      }
      echo $btn;
    ?>
  </div>
</form>