function frontier_preview_post($tmp_post_id = 0)
{
    $concat = get_option("permalink_structure") ? "?" : "&";
    //fp_log("Post id (preview): ".$tmp_post_id);
    frontier_post_output_msg();
    $preview_post = get_post($tmp_post_id);
    //post variable: $preview_post
    $tmp_content = apply_filters('the_content', $preview_post->post_content);
    $tmp_content = str_replace(']]>', ']]>', $tmp_content);
    include_once frontier_load_form("frontier_post_form_preview.php");
}
<?php

//Display message
frontier_post_output_msg();
global $ns_blog_user;
if (strlen($frontier_edit_text_before) > 1) {
    echo '<div id="frontier_edit_text_before">' . $frontier_edit_text_before . '</div>';
}
//***************************************************************************************
//* Start form
//***************************************************************************************
echo '<div class="frontier_post_form"> ';
echo '<form action="' . $frontier_permalink . '" method="post" name="frontier_post" id="frontier_post" enctype="multipart/form-data" >';
// do not remove this include, as it holds the hidden fields necessary for the logic to work
include FRONTIER_POST_DIR . "/forms/frontier_post_form_header.php";
wp_nonce_field('frontier_add_edit_post', 'frontier_add_edit_post_' . $thispost->ID);
?>
	<table class="frontier-post-taxonomies"><tbody><tr>
	<td class="frontier_no_border">
	<fieldset id="frontier_post_fieldset_title" class="frontier_post_fieldset">
		<legend><?php 
_e("Title", "frontier-post");
?>
</legend>
		<input class="frontier-formtitle"  placeholder="<?php 
_e('Enter title here', 'frontier-post');
?>
" type="text" value="<?php 
if (!empty($thispost->post_title)) {
    echo $thispost->post_title;
}