QA Ultimate Stack
When the test machine itself blocks the tags
A security or ad-blocking tool on the computer running the test can quietly swap the Google tag library for a stub, so the page sends nothing. How ODDVX flags it, and what to do before trusting a zero.
A zero that isn't the site's fault
Some VPNs' threat-protection features, ad blockers and filtering proxies intercept HTTPS traffic on the computer they run on. A few replace Google's tag library, gtm.js or gtag.js, with a small stub script. The page still loads, but no tags fire and no hits are sent. To the test, the site looks completely broken.
Two panels comparing the real Google tag library with a locally substituted stub that sends nothing.
ODDVX checks the library, not just the hits
The Network Requests Inspector checks whether the tag library the page received is really Google's. If it isn't, the page diagnosis says NOT the Google library (replaced locally) instead of reporting a broken site, so you don't send developers chasing a problem that only exists on your computer.
A page diagnosis showing zero collect requests and a flag that the Google tag library was replaced locally.
Tell a local block from a real one
The diagnosis names the file that was replaced and how many bytes came back. Google's real library is many kilobytes; a stub is tiny. Other signs point the same way:
- Every brand fails at once, on sites with different containers and hosting. Real breaks are rarely that uniform.
- The live site works in your normal browser, or from a different network, but not in the test.
- The failures started when a tool was installed or updated, often a VPN, antivirus web protection or a corporate proxy, not after a release.
If the library is genuine and the page still sends nothing, the cause is on the site. Work through the other reasons in the page diagnosis: no container on the template, consent not granted, a trigger needing interaction, or a CSP block.
A page diagnosis checklist for a page with zero collect requests, with the locally replaced library marked as not the site's fault.
Clear it and run again
- Look for the replaced-library flag on any page with zero hits.
- Pause the tool doing the replacing: threat protection in your VPN, an ad blocker, or a filtering proxy.
- Run the page again.
- If hits now appear, the site was fine all along.
Four steps to clear a local tag blocker and confirm the site was fine.
ODDVX for Windows
From the page to the hit, proved.
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