shell bypass 403
<?php
defined( 'ABSPATH' ) or exit;
// fake post to prevent notices in wp_enqueue_scripts call
$GLOBALS['post'] = new \WP_Post( (object) array( 'filter' => 'raw' ) );
// render simple page with form in it.
?><!DOCTYPE html>
<html>
<head>
<title>Mailchimp for WordPress Form Preview</title>
<meta charset="utf-8" />
<meta name="robots" content="noindex" />
<link type="text/css" rel="stylesheet" href="<?php bloginfo( 'stylesheet_url' ); ?>" />
<?php
wp_enqueue_scripts();
wp_print_styles();
wp_print_head_scripts();
if ( function_exists( 'wp_custom_css_cb' ) ) {
wp_custom_css_cb();
}
?>
<style>
body{
background: white;
width: 100%;
max-width: 100%;
text-align: left;
}
/* hide all other elements */
body::before,
body::after,
body > *:not(#form-preview) {
display:none !important;
}
#form-preview {
display: block !important;
width: 100%;
height: 100%;
padding: 20px;
border: 0;
margin: 0;
}
</style>
</head>
<body class="page-template-default page ">
<div id="form-preview" class="page type-page status-publish hentry post post-content">
<?php mc4wp_show_form( $form_id ); ?>
</div>
<?php wp_footer(); ?>
</body>
</html>