/home/sylamedg/www/wp-content/plugins/unbounce/templates/settings_response_headers_forwarded.php
<textarea
name="<?php echo UBConfig::UB_RESPONSE_HEADERS_FORWARDED_KEY; ?>"
rows="<?php echo count($value); ?>"
data-default="<?php echo esc_attr(implode(PHP_EOL, $default)); ?>"
class="ub-settings-input"><?php echo sanitize_textarea_field(implode(PHP_EOL, $value)); ?></textarea>
<p class="description">
Each line represents an HTTP header sent by Unbounce that is allowed to be forwarded to visitors. In order to forward all headers, set this field to <code>*</code>.
<strong>Note:</strong> the following headers are always forwarded whether they are listed or not:
<?php
$headers = array_map(function ($header) {
return '<code>'.$header.'</code>';
}, get_option(UBConfig::UB_DYNAMIC_CONFIG_CACHE_KEY, array())['response_header_allow']);
echo implode(',', array_slice($headers, 0, -1)).' and '.end($headers);
?>
</p>