• Adwords remarketing tag
• Event tracking
• Google Tag Manager
• Cookies and user ID
• UserID with Google Tag Manager
• GTM + Enhanced Ecommerce (UA)

The scripts included by GTM are added before the first script in the page. So with the plans de marquages where we have to put some script before the gtm js we can't make it work.

Solution : change the way the GTM js is called. The following code append the gtm into the head (it's supposed to be at the end but only goes just after the js which call it, but that still work).

(function(w,d,s,l,i)
{
	w[l]=w[l]||[];w[l].push({'gtm.start': new Date().getTime(),event:'gtm.js'});
	var f=d.getElementsByTagName('head')[0],
	j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';
	j.async=true;j.src='//www.googletagmanager.com/gtm.js?id='+i+dl;
	f.appendChild(j);
})(window,document,'script','dataLayer','GTM-XXXXXXX');

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