container audit

GTM-M8GN9BJM

This container ships 69 hand-written scripts (121 KB of JavaScript) to every visitor — more than 96% of the 46,522 containers we have measured. That is an application's worth of code, delivered as tag configuration.

Measurement runs through a server container on its own domain — the mark of a mature setup, and rarer than the tooling vendors imply.
331 published versions — each one live for every visitor the moment it was published.
inner-html is uncommon — under 6% of the containers we have measured have it. That is context rather than a verdict: a server container is rarer still and is a sign of a mature setup. What it means is in the finding itself.

Tags126

Custom scripts69

Third parties30

Delivered782 KB

Versions331

What we observed

A real browser loaded giftcards.com a month ago and recorded every request it made. This is what happened, as distinct from what the container is configured to do. It is one page load — anything that fires only deeper in the site did not fire here.

Container loaded from collect.giftcards.com — the site's own host, and googletagmanager.com

Measurement sent to collect.giftcards.com — not Google

Measurement runs through the site's own infrastructure. Part of the tag library still comes from Google, which is normal — the two are loaded separately.

Forwarded to GA4 ×4 — read from the measurement id, not the hostname

Consent a consent platform is present, but our browser could not complete the accept step — so the before-and-after comparison did not run here. Google recorded gcs=G111 (all granted).

Third parties contacted 25 hosts — cdn.jsdelivr.net, dd.blackhawknetwork.com, consent.trustarc.com, client.px-cloud.net, assets.adobedtm.com, trustmark.prod.security.blackhawknetwork.com, unpkg.com, adobedc.demdex.net, and 17 more

dataLayer events seen gtm.js, nantu_page_view, gtm.dom, gtm.load

Where the data goes

Confirmed — a browser watched this site send measurement data to collect.giftcards.com, not to Google. observed on giftcards.com More info »

Findings

Ordered by consequence. review has a concrete cost when it bites; info is real but depends on your setup. Seen is how common it is across the containers we have measured — reported separately on purpose, because common and harmless are different claims.

reviewdocument.write (8)

8 pieces of custom code call document.write.

Whydocument.write blocks the HTML parser while it runs, and browsers ignore it entirely once the page has finished parsing — so an async-loaded tag using it can silently do nothing.

CheckIf these tags fire on page load they are costing render time; if they fire later they may not be working at all. Worth confirming the tag still does what it was added to do.

Seenseen in 18.4% of 46,522 containers measured

reviewWrites cookies directly (4)

4 pieces of custom code set cookies in code.

WhyCookies set this way bypass GTM's consent settings, because the consent checks live in the tag templates rather than in raw JavaScript.

CheckIf any of these cookies are used for analytics or advertising, confirm they are still gated on a consent decision.

Seenseen in 21.2% of 46,522 containers measured

reviewWrites innerHTML (3)

3 pieces of custom code assign to innerHTML.

WhyAssigning innerHTML parses the string as HTML. If any of it comes from the URL, the page or a cookie, that is a script-injection route into your own site.

CheckCheck whether the assigned value is a fixed template or built from something a visitor can influence.

Seenseen in 5.7% of 46,522 containers measured

infoLoads JavaScript from another host (18)

18 pieces of custom code fetch and run JavaScript from another host.

WhyWhatever that host serves executes with full access to the page — it can read the DOM, cookies and form fields. The code is not in this container, so it can change at any time without any change here.

CheckConfirm you recognise every host below and that someone owns the relationship. A host you cannot name is the one to chase.

Seenseen in 54.4% of 46,522 containers measured

infoUses browser storage (17)

17 pieces of custom code read or write localStorage or sessionStorage.

WhyBrowser storage persists across visits and is not covered by cookie consent tooling, so it is easy to overlook when auditing what you keep on a visitor's device.

CheckConfirm nothing personal is being kept there, and that it is covered by your privacy notice.

Seenseen in 23.3% of 46,522 containers measured

infoConsent configuration detected (4)

The container declares one or more consent signals.

WhyConsent handling is present in the container. This describes what the artifact declares; what actually happened on the page is measured separately, above.

CheckConfirm these settings match the consent policy you intend to enforce, and compare them with the before-and-after observation.

Seenseen in 44.6% of 46,522 containers measured

Third parties it can reach

Each host is a party that can execute code or receive data in a visitor's browser. Follow one to see who else loads it. More info »

What the custom templates can do

Custom templates are third-party code shipped inside the container. Injecting scripts and running page globals is ordinary for them — most tag templates need it to work — so this is an inventory, not a warning. It lists the capability each template declares so you can match it against templates you meant to install.

__cvt_172524090_477 private runs page-level globals

__cvt_172524090_571 private injects code from www.clarity.ms · runs page-level globals

__cvt_5RFHV gallery injects code from consent.trustarc.com · runs page-level globals

__cvt_172524090_529 private injects code from x.rokt.com

__cvt_172524090_767 private injects code from dynamic.criteo.com

__cvt_172524090_807 private injects code from gtm.adt313.net

__cvt_172524090_812 private injects code from gtm.adt313.net · runs page-level globals

__cvt_579DB gallery runs page-level globals

__cvt_5RM3Q gallery injects code from connect.facebook.net, capi-automation.s3.us-east-2.amazonaws.com · runs page-level globals

__cvt_PBGZL gallery injects code from www.redditstatic.com · runs page-level globals

__cvt_T5P92 gallery injects code from js.adsrvr.org

Detected on

Sites observed loading this container. A container used across many hosts is a shared template; one on a single host is a bespoke build. Follow a site to see every container it loads.

giftcards.com

What this audit describes

Containers change. These findings describe one specific artifact, and you can re-fetch it to check this reading.

Container	`GTM-M8GN9BJM`
Published version	`331` — the identity of this configuration. It changes only when someone publishes.
Read at	2026-08-12 22:28:18 UTC (a month ago)
Source	`https://www.googletagmanager.com/gtm.js?id=GTM-M8GN9BJM`
Body checksum	`7bfbcaecdb921db6c55675344fa0afa1de8d3b1bf1fb6d11acbd0544ddeb5a0e` Evidence of the exact bytes we read, not an identity: Google varies the response per request, so re-fetching an unchanged container yields a different checksum. Compare the published version instead.

Re-audit

This reading is from a month ago. A container can be republished at any time, and nothing here updates on its own — a fresh read is the only way to know whether it still says this. Running it again replaces this page in place, so the link keeps working.

Re-audit GTM-M8GN9BJM

Check another container

Put this container under version control. Tagora exports it to a repository you own, so every change arrives as a pull request. How it works »