function addSlashes( str ) {
    return (str + '').replace(/'/g, '\"').replace(/\n/g, '\\n');
}

var newTag = addSlashes(`<!-- Facebook Pixel Code -->
<script>
if (document.location.href.search('gtm-msr.appspot') == -1) {
!function(f,b,e,v,n,t,s){if(f.fbq)return;n=f.fbq=function(){n.callMethod?
n.callMethod.apply(n,arguments):n.queue.push(arguments)};if(!f._fbq)f._fbq=n;
n.push=n;n.loaded=!0;n.version='2.0';n.queue=[];t=b.createElement(e);t.async=!0;
t.src=v;s=b.getElementsByTagName(e)[0];s.parentNode.insertBefore(t,s)}(window,
document,'script','https://connect.facebook.net/en_US/fbevents.js');
fbq('init', 'XXXXXXXXXXXXXXXX'); // Insert your pixel ID here.
fbq('track', 'PageView');
}  
</script>
<noscript><img height="1" width="1" style="display:none"
src="https://www.facebook.com/tr?id=2005179879722847&ev=PageView&noscript=1"
/></noscript>
<!-- DO NOT MODIFY -->
<!-- End Facebook Pixel Code -->`);

console.log(newTag);