You may not know that recent changes in Ad and Content blocking mean your marketing website may not be functioning as expected. Key tracking metrics may not be a true reflection of your website’s traffic and worse, you could be missing out on leads.

Key issues

Ad blockers can interfere with your gates in three separate ways:

  1. Tag management platforms, such as Google Tag Manager, are blocked. This means that if you are including the script through such a platform, it may fail to load.
  2. Tracking scripts from marketing platforms such as Eloqua are blocked. This means that pre-population may fail to function correctly.
  3. Domains associated with marketing platforms such as Eloqua are blocked. This means that form submissions may fail to complete successfully as these often route through these domains.

It is important to note that ad blockers do not directly target the domain. They interfere with gates and form submissions by targeting supporting services such as Google Tag Manager or Eloqua. You would experience these same issues if you are utilising these platforms, regardless of whether you are also using

A bit of background

Starting with Firefox 65, which was first offered to Release channel users on 29th January 2019, users now have 3 modes for content blocking. Any users who opt to use “strict” mode will automatically block most tag management tools like Google Tag Manager, Tealium and Adobe Tag Manager. In addition, plugins such as Ghostery and new browsers like Brave provide the same blocking functionality. The impact of this is that standard analytics, usually injected through tag management technology may not now be recording page hits and other user interactions on your website.

Even worse, if your website is reliant on style sheets injected in the same way, the user experience may be vastly different from your marketing department’s official brand guidelines. Layouts will default to browser base standards, mobile responsive capability could be lost and components could simply fail to display.

Ad blockers provided by browser extensions such as Ad Block Plus and uBlock also block tag managers and other technologies depending upon how the user configures the extensions settings. 

Subtler issues may go unnoticed, for example, AJAX requests may return unexpected results depending upon the blocking technology being used by the browser/extension. Forms may even be posting data that gets blocked, meaning you’re losing important lead information.

This is all on top of the major issue that ad blockers can cause: forms failing to load or submit correctly, and therefore data loss.

Most of the blocking is based upon the domain name or by matching elements of the path and file name of the resources being requested. The rules are often maintained as public resources such as EasyList [] and are available for anyone to use. Other tools may have their own proprietary methods.

You may be able to circumvent some of the blocked resources by simply hosting them in your own domain which hopefully shouldn’t be listed. Other resources, such as tag manager output, cannot currently be loaded via alternative domains and you’re therefore stuck with using them. In addition, some browsers such as Brave will block some marketing scripts even if they are hosted from alternative domains.

Solutions for using with ad blockers

  1. Do not use tag managers to inject the Script. Instead, use the best practice guidelines found here. This ensures that gates can load correctly even in the presence of ad blockers. 
  2. Use a custom domain mapped to your Marketing Automation Platform account for all form submissions.
  3. Utilise's built-in ad blocking functionality and display a warning message to affected users (detailed below).

If the script has loaded, it is able to check for the possible presence of ad and privacy blockers and display a warning message to users. This is an optional feature that must be activated by your account manager. If active, then we will attempt to load an asset such as an image that is hosted on the same domain as your Marketing Automation platform. If this asset fails to load, this is a good indication that privacy blocking is running and has blocked this asset from loading. When this happens, we will display a customisable message to affected users above each form.

In addition, the forms themselves can be disabled and prevented from submitting. Whilst this is a good way to prevent lost submissions, false positives can also prevent normal users from submitting forms, so this feature should be used with care.

In order to activate this feature you will need to supply us with the URL of an asset hosted (e.g. a 1px gif image) on the same domain that your Marketing Automation Platform runs from. If this file can be loaded, then it is assumed that any form submissions will also be able to be sent to this domain correctly. Note that if you subsequently rename or remove the asset, it will fail to load correctly and will trigger the privacy blocking message for all users.

If you are unable to provide a custom asset we can instead try to loading one of the relevant tracking scripts below, however this option is less optimal as it does not take into account any custom domains mapped on your account, and may fail even where a form submission would other succeed:


Solutions for other platforms

If you have no choice other than to use Tag Managers to host your scripts, and therefore there is a risk that the script may not load - or if you are experiencing issues with features of other platforms being blocked - you can use a utility script we have created to display a message to your users in the case of content blocking.

We’ve developed a simple script you can add to web pages that you can use to detect ad and privacy blockers. This script uses the same basic approach we have outlined above. Due to the nature of ad blockers, you won’t be able to inject this into all your pages with a tag manager, so you’ll have to include it into selected pages as needed or have your web server or CMS system include it as a default script.

<script src=””></script>

You can then add some additional script to test for different MarTech tools depending upon which ones you use. We currently have tests for the following :

Adobe Tag Manager, Autopilot, Eloqua, Facebook, Google Analytics, Google Tag Manager,, Hubspot, Linkedin, Marketo, Pardot, Tealium, Twitter and Woopra.

We’ve even built an example for you to test with. This is built using one of bootstrap’s standard template pages and jQuery. You can try it online here or save it locally to experiment with it further.