tagora
container audit

GTM-MJRRRXXR

This container ships 74 hand-written scripts (38 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.

Tags131
Custom scripts74
Third parties13
Delivered555 KB
Versions83

What we observed

A real browser loaded canon.jp 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 no consent gate responded on this page, so there was nothing to hold measurement back (banners are often shown only to visitors in certain regions, and this was not a European visit).
Third parties contacted 9 hosts — fonts.googleapis.com, www.googletagmanager.com, www.google.co.il, analytics.google.com, stats.g.doubleclick.net, www.google-analytics.com, s.yimg.jp, www.google.com, and 1 more
dataLayer events seen gtm.js, gtm.click, gtm.dom, gtm.load, gtm.scrollDepth

Where the data goes

Not observed — on the page we loaded, measurement went to Google and nowhere else. observed on canon.jp 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 (73)
73 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

reviewSame Google Ads conversion defined more than once (7)
1 conversion action is defined by more than one tag.

WhyA conversion ID plus label identifies one action. Two tags carrying the same pair can report the same conversion twice, inflating conversion counts and the ROAS that bidding runs on.

CheckCheck whether both tags can fire on the same page. If they can, your Ads reporting is overstating this action and automated bidding is optimising against it.

Seenseen in 3.8% of 46,522 containers measured

infoLoads JavaScript from another host (28)
28 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 (1)
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 »

www.googleadservices.com ×30googleads.g.doubleclick.net ×24s.yimg.jp ×14i.smartnews-ads.com ×11cd.ladsp.com ×8connect.facebook.net ×6www.facebook.com ×6cdn.smartnews-ads.com ×5serving-pa.admatrix.jp ×5assets.gunosy.com ×4bat.bing.net ×2c.amazon-adsystem.com ×1www.google-analytics.com ×1

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.

canon.jp

What this audit describes

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

ContainerGTM-MJRRRXXR
Published version83 — the identity of this configuration. It changes only when someone publishes.
Read at2026-08-22 10:24:33 UTC (a month ago)
Sourcehttps://www.googletagmanager.com/gtm.js?id=GTM-MJRRRXXR
Body checksum8721008f1aba0a98a5aee7f6d8af0662a6c149cb1d2be7a11639424e85fb5d69
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-MJRRRXXR

Check another container

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