container audit

GTM-M847L7

This container ships 150 hand-written scripts (91 KB of JavaScript) to every visitor — more than 99% of the 46,522 containers we have measured. That is an application's worth of code, delivered as tag configuration.

1,770 published versions — each one live for every visitor the moment it was published.
duplicate-ga4-config is uncommon — under 5% 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.

Tags254

Custom scripts150

Third parties38

Delivered727 KB

Versions1770

What we observed

A real browser loaded premium-water.net 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 googletagmanager.com — Google

Measurement sent to google-analytics.com — Google

Consent a consent banner was present and we accepted it. 4 measurement hits left the page before it was granted, carrying a client id (whether that is permitted depends on jurisdiction, and this was not a European visit). 2 hosts appeared only after consent was granted. Google recorded gcs=G1 (no consent signal). 10 advertising hosts were contacted before anything was granted.

Third parties contacted 25 hosts — cdnjs.cloudflare.com, fonts.googleapis.com, show.revico.jp, www.googletagmanager.com, cdn-edge.karte.io, s.yimg.jp, bat.bing.com, static.ads-twitter.com, and 17 more

dataLayer events seen gtm.js, gtm.dom, gtm.scrollDepth, gtm.click, gtm.linkClick, gtm.load

Where the data goes

Not observed — on the page we loaded, measurement went to Google and nowhere else. observed on premium-water.net 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 (3)

3 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

reviewHardcoded http:// URL (3)

3 pieces of custom code reference a plain http:// address.

WhyOn an https:// page the browser blocks or upgrades these. Blocked means the tag quietly stops working; upgraded only works if that host also serves https.

CheckCheck whether the hosts below still respond over https, and update the URLs.

Seenseen in 12.8% 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

reviewWrites cookies directly (2)

2 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

reviewSame GA4 property configured more than once (1)

G-MQBC47XNN3 is configured by 2 separate tags.

WhyEach config tag initialises the property independently, so a single page view can be counted once per tag. Sessions, users and conversion rates all inherit the error.

CheckIf more than one of these fires on the same page you are double-counting. Compare against a known-good day, or check for a step change in traffic when the second tag was added.

Seenseen in 4.8% of 46,522 containers measured

infoLoads JavaScript from another host (45)

45 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

infoVendor IDs written into custom code (4)

4 vendor IDs are pasted directly into custom HTML rather than held in a variable or template.

WhyChanging a property, pixel or account then means editing every tag that mentions it, and any one that gets missed keeps sending to the old destination indefinitely.

CheckFine if the ID never changes. If you have ever migrated a property, check that none of these still point at the old one.

Seenseen in 31.4% of 46,522 containers measured

infoConsent configuration detected (2)

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

infoUses browser storage (1)

1 piece 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

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_1097590_1013 private injects code from s.yimg.jp · runs page-level globals

__cvt_1097590_1014 private injects code from s.yimg.jp · runs page-level globals

__cvt_1097590_1022 private injects code from s.yimg.jp · runs page-level globals

__cvt_1097590_1024 private injects code from www.clarity.ms · runs page-level globals

__cvt_1097590_1447 private injects code from s.yimg.jp · runs page-level globals

__cvt_1097590_1448 private injects code from s.yimg.jp · runs page-level globals

__cvt_1097590_1450 private injects code from static.ads-twitter.com · runs page-level globals

__cvt_1097590_1451 private injects code from static.ads-twitter.com · runs page-level globals

__cvt_1097590_1453 private runs page-level globals

__cvt_579DB gallery runs page-level globals

__cvt_KT9RV gallery injects code from dynamic.criteo.com

__cvt_T9LDK gallery injects code from x.eisa.mercari.com · runs page-level globals

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.

premium-water.net

What this audit describes

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

Container	`GTM-M847L7`
Published version	`1770` — the identity of this configuration. It changes only when someone publishes.
Read at	2026-08-13 11:33:39 UTC (a month ago)
Source	`https://www.googletagmanager.com/gtm.js?id=GTM-M847L7`
Body checksum	`10103ee5fa361eb2acd8e9a82589a3e4fb2e45f45ed230566a8e6f2a7c8141a9` 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-M847L7

Check another container

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