facebook-conversion-pixel-with-custom-post-widget.php

<?php
/*
Plugin Name: Add Facebook Conversion Pixel with Custom Post Widget
Description: Add Facebook Conversion Pixel with Custom Post Widget
Version: 1.0
Author: Kellen Mace
Author URI: http://kellenmace.com/
License: GPLv2 or later
License URI: http://www.gnu.org/licenses/gpl-2.0.html
*/

function fb_pxl_for_custom_post_widget() {
	global $post;

	// Bail if the content of this page doesn't include a content_block shortcode
	if ( ! has_shortcode( $post->post_content, 'content_block' ) {
		return;
	}

	// If user has enabled the content_block post type, insert conversion pixel code
	if ( isset( $fb_pxl_options[ 'content_block' ] ) && 'on' === $fb_pxl_options[ 'content_block' ] ) {

		$fb_pxl_code = "

		PASTE CONVERSION PIXEL CODE HERE

		";
		echo $fb_pxl_code;
	}
}
add_action( 'wp_head', 'fb_pxl_for_custom_post_widget' );