Update 17 February 2020: Google Tag Manager’s Preview mode cookies have been updated with the necessary flags, so they will not break once SameSite enforcement begins. If you’ve opened the browser console in Google Chrome (since Chrome 76), you might have seen a bunch of warnings in a yellow background related to something called a SameSite cookie attribute that is either missing or incompletely set for cookies set on external domains.

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Google Tag Manager now lets you add unit tests directly to your custom templates. This is useful, since it allows you to control the code stability of your templates, especially if you’ve decided to share those templates with the public. I recently shared a general guide for how template tests work, but I wanted to expand the topic a little, and share with you two walkthroughs of custom template tests: one for a variable template and one for a tag template.

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I’ve written about outbound link click tracking before. It’s a very solid way to track interactions on the site, as clicking a link that leads away from a site is a signal of … well, something. In Google Tag Manager it’s now extremely easy and efficient to track outbound link clicks, thanks to the introduction of a new configuration in the Auto-Event variable. This article will introduce the new method and show you how you can quickly set it up!

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When previewing Custom HTML tags in Google Tag Manager you’ve almost certainly run into a situation where the GTM variable shows up as a weird JavaScript method resembling something like this: google_tag_manager["GTM-ABCD123"].macro(15) And this is when you were expecting it to show the actual, resolved value! It doesn’t help that every now and then the preview mode actually shows to correct value in the preview mode. What’s up with that? Well, there’s a fairly logical explanation to this.

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A surprisingly common question in forums and communities seems to be why the built-in Click variables show up as undefined in Google Tag Manager’s Preview mode, even if you click around the site. In this article, I’ll walk you through some of the reasons why this might happen. Tip 104: What to do when Click variables are undefined Here’s the situation: you want to create a Click trigger for your tags, but in order to do so, you’d need to see what values the built-in Click variables (e.

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It’s been a while since I’ve last written a bona fide Google Tag Manager trick, so here comes. This was inspired by Bart Gibby’s question in Measure Slack. The purpose is to fetch the latest currency exchange rates from the exchangeratesapi.io service, cache them using sessionStorage, and push the results into dataLayer. From dataLayer, they can then be utilized in Custom JavaScript variables and custom variable templates to perform client-side conversions.

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With Intelligent Tracking Prevention, the Safari browser is on a crusade against cross-site tracking. One of the most obvious and long-standing ways to battle cross-site tracking has been to block third-party cookies in the web browser, and this is exactly what Safari does by default. However, Google Tag Manager’s Preview mode relies on a third-party cookies, so that it can serve you the draft version of the container while serving the regular, live container to your site visitors.

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