container audit

GTM-MC8ZX4F

46 tags, 5 custom scripts, 3 third-party hosts — an ordinary container, near the middle of what we measure (median: 39 tags, 4 custom scripts).

5 custom HTML tags carrying 4 KB of JavaScript. This runs on every page the container loads on.
3 third-party hosts reachable from its tags.
Measurement runs through a server container on its own domain — the mark of a mature setup, and rarer than the tooling vendors imply.

Tags46

Custom scripts5

Third parties3

Delivered564 KB

Versions134

What we observed

A real browser loaded active24.cz 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 datainsights.active24.cz — not Google

Measurement is first-party; the container still loads from Google. These are separate decisions, and this is the more common of the two.

Forwarded to GA4 ×2 — 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 — maps.googleapis.com, www.googletagmanager.com, sentry.websupport.sk, active24.ladesk.com, cdn.iubenda.com, eu.acsbapp.com, embeds.acswapp.com, srv.isy-teamblue.services, and 17 more

dataLayer events seen gtm.js, page_view, gtm.dom, iubenda_gtm_consent_event, gtm.triggerGroup, gtm.load

Where the data goes

Confirmed — a browser watched this site send measurement data to datainsights.active24.cz, not to Google. observed on active24.cz 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.

reviewWrites cookies directly (1)

1 piece 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

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

infoLoads JavaScript from another host (1)

1 piece 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

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 »

analytics.tiktok.com ×1 c.seznam.cz ×1 srv.isy-teamblue.services ×1

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_KFGZD gallery injects code from cdn.iubenda.com, embeds.iubenda.com

__cvt_5NG3N gallery injects code from c.seznam.cz · 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_8258065_169 private injects code from static.ads-twitter.com · runs page-level globals

__cvt_8258065_236 private injects code from snap.licdn.com

__cvt_8258065_243 private 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.

active24.com active24.cz

What this audit describes

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

Container	`GTM-MC8ZX4F`
Published version	`134` — the identity of this configuration. It changes only when someone publishes.
Read at	2026-08-12 22:28:49 UTC (a month ago)
Source	`https://www.googletagmanager.com/gtm.js?id=GTM-MC8ZX4F`
Body checksum	`a6d675c102cbec80c01a0b0bbe5a47bbaa85d3be35428fba1525a51d5addbc48` 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-MC8ZX4F

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 »