One of the features available on CleanBrowsing is the ability to block ad and tracking domains. Our Ads/Tracking filter is designed to block domains that have been used, and flagged, for some form of data collection and/or advertisements. It is an optional filter that you can enable on any of the paid plans.

The Problem with Blocking Tracking Domains

Although blocking ad and tracking domains sounds like a straightforward improvement, complications arise when tracking infrastructure serves dual purposes. Some websites integrate tracking and analytics code so deeply into their architecture that blocking those domains can degrade performance or even prevent pages from loading entirely.

The challenge is that many sites have built dependencies on third-party services like Google Analytics, tag managers, and advertising platforms. When these domains are blocked at the DNS level, the site may hang while waiting for responses that will never come, resulting in slow load times or broken functionality.

Real-World Example: Rabobank

A good example of this issue was observed with the Rabobank website. When the Ads/Tracking filter was enabled, three domains were blocked: tags.tiqcdn.com, www.google-analytics.com, and www.googletagmanager.com. While the site appeared to function normally on the surface, there was noticeable performance degradation as the browser waited for these blocked resources.

How to Identify Affected Domains

If you suspect that blocking ads and trackers is impacting a website you rely on, there are two ways to diagnose the issue:

• Compare the browser developer tools output with the filter enabled versus disabled. Look for requests that are timing out or failing.
• Review the "Blocked Requests" section in your CleanBrowsing dashboard to see which tracking domains are being blocked for the sites you visit.

Solutions

If you determine that certain tracking domains are essential for a site to function properly, CleanBrowsing offers two solutions:

• Disable the filter: You can turn off the Ads/Tracking filter entirely from your CleanBrowsing dashboard.
• Whitelist specific domains: Use the "Custom Allow" feature to whitelist the specific domains that are causing issues while keeping the rest of the filter active.

The whitelist approach is generally recommended, as it allows you to maintain the benefits of ad and tracker blocking while resolving issues with specific sites that depend on those services.