nextcloud-server/core/templates/untrustedDomain.php

<?php /** @var $_ array */ ?>

<ul class="error-wide">
	<li class='error'>
		<?php p($l->t('You are accessing the server from an untrusted domain.')); ?><br>

		<p class='hint'>
			<?php p($l->t('Please contact your administrator. If you are an administrator of this instance, configure the "trusted_domains" setting in config/config.php. An example configuration is provided in config/config.sample.php.')); ?>
			<br>
			<?php p($l->t('Depending on your configuration, as an administrator you might also be able to use the button below to trust this domain.')); ?>
			<br><br>
			<p style="text-align:center;">
				<a href="<?php print_unescaped(\OC::$server->getURLGenerator()->getAbsoluteURL(\OCP\Util::linkToRoute('settings.AdminSettings.index'))); ?>?trustDomain=<?php p($_['domain']); ?>" class="button">
					<?php p($l->t('Add "%s" as trusted domain', array($_['domain']))); ?>
				</a>
			</p>
		</p>
	</li>
</ul>