Track Interactions in the Shadow DOM Using Google Tag Manager

The shadow DOM is a way to add HTML structures to the web page so that they remain isolated from the rest of the document object model (DOM). It’s a popular concept with web components, as it allows for encapsulation of web structures so that they aren’t affected by style declarations of the parent tree, for example. However, being such a “hidden” structure, anything that happens in the shadow DOM is also hidden from Google Tag Manager’s listeners. Read More…

#GTMTips: Simple Way to Exclude Internal Visits From Google Analytics

With so many people working from home or remotely in these turbulent times, it’s time to revisit one of my oldest articles, and discuss the options you have for excluding or segmenting internal traffic in Google Analytics. The traditional method of IP address exclusion is not necessarily the best option anymore, unless all your employees use a specific VPN to connect to the site. In this article, we’ll go through some of the tools you have at your disposal. Read More…

The New CookieFlags Setting in Google Analytics

With the enforcement of SameSite settings in the latest versions of Google Chrome, it’s become a mad scramble to get cookies working across first-party and third-party contexts. I’ve covered this phenomenon before in my SameSite article, as well as in my guide for setting up cookieless tracking for iframes. Recently, Google Analytics updated its libraries (App+Web, gtag.js, and analytics.js) with a new setting: cookieFlags (analytics.js) or cookie_flags (App+Web and gtag.js). Read More…

Send Hits to the Past With Google Analytics

One of the hard-and-fast rules in Google Analytics is that once hits have been collected and processed into your data properties, those hits are untouchable. This means that if you mistakenly collect duplicate or incorrect transactions, PII traffic, or referral spam, for example, it’s extremely difficult, if not downright impossible, to purge or change this data in Google Analytics. Another staple of Google Analytics’ strict schema is that displacing hits in time is also very difficult. Read More…

Create Slack Notification System for Google Tag Manager Changes

Until recently, I had a feature on GTM Tools that polled the user’s Google Tag Manager container(s) for a recently published version. If one was found, a notification was sent to a Slack app, which forwarded it to a workspace and channel of the user’s choice. This was fine, except for the fact that polling the GTM and Slack APIs for dozens upon dozens of containers is a total resource hog, and the only way I can maintain GTM Tools is it doesn’t have API leaks like that. Read More…

Cookieless Tracking for Cross-Site Iframes

Updated 25 May 2021: Added information about using this with GA4. As Google Analytics 4 does not have a mechanism to disable cookie storage, only the second solution (send dataLayer events from iframe to the parent) described in this article will work for GA4. Here I am, back with <iframe> and cross-domain tracking. I’ve published a couple of articles before on the topic, with my upgraded solution being the most recent one. Read More…

The Custom HTML Tag Guide for Google Tag Manager

One of the most prominent features of Google Tag Manager since the dawn of time (actually, late 2012) is the Custom HTML tag. This little piece of magic lets Google Tag Manager inject an HTML element to the page. Since time immemorial (still late 2012), it’s allowed us to turn Google Tag Manager from a sandboxed prisoner of the native tag templates to a no-holds-barred client-side content management solution. In this article, we’ll discuss how the Custom HTML tag works, and what you might be tempted to use it for. Read More…

CDNJS Hosted Libraries Template for Google Tag Manager

One of the prime things to use Google Tag Manager for is script injection. Loading a third-party JavaScript library is trivial to do with a Custom HTML tag, and works like a charm. However, using Custom HTML tags for, well, anything, is no longer the preferred way to add custom code to the site. Custom HTML tags are pretty expensive DOM injections, and they can be incredibly dangerous tools (for UX, security, and privacy) in the wrong and/or inexperienced hands. Read More…

Fetch IP Geolocation Data Using Google Tag Manager

Update 6 April 2020: I updated the template in the gallery to the latest version of the IP Geolocation API SDK, which no longer requires jQuery. Also, the SDK now handles API request caching to browser storage automatically, so the “Enable Session Storage” option was added to the template. My latest custom tag template tackles a use case I’ve referred to a number of times before, especially in my article on sending weather data to Google Analytics. Read More…

Persist Campaign Data on the Landing Page

Universal Analytics utilizes two components (by default) to attribute a browser session to a specific campaign: query parameters in the URL and the referrer string. The page URL is sent with every hit to Google Analytics using the Document location field, which also translates to the &dl parameter in the Measurement Protocol. The referrer string is sent with a hit to Google Analytics using the Document referrer field, as long as the referrer hostname does not exactly match that of the current page and the referrer string is not empty. Read More…