A worker reports the same client hints as the page
A dedicated worker's userAgentData and its high-entropy values equal the page's. N/A where either realm cannot read them (severity: warn).
What a detector infers
navigator.userAgentData exists in dedicated workers too, and it reads the same browser-wide values as the page: the same brands, platform and mobile flag, and the same high-entropy answers. A value rewritten in the page's JavaScript does not reach the worker, which has its own global, and some overrides apply only to the page target.
The existing worker rows compare the user agent, platform, CPU count and memory; this one compares the client hints, field by field: brands, platform, mobile, architecture, bitness, platformVersion, uaFullVersion and the full version list. Measured on 2 November 2026 on Windows: genuine Chrome 156 and Clearcote report identical hints in both places.
How to resolve it
Change client hints in the browser rather than in the page, so that every realm reads the same values.
Other checks in Worker realms
- Every worker realm reports the same identity as the window
worker-realms-agreeA page is not one JavaScript realm — it is several. The audit loads one probe script into all three worker kinds the platform offers: a… - Every worker realm reports the same GPU as the window
worker-gpu-agreesInside each worker the probe creates an OffscreenCanvas(32,32), obtains a webgl (or experimental-webgl) context, and reads… - Worker scopes available to compare against the window
worker-scopes-reachedThis row asserts nothing — pass is hardcoded null and severity is info. - The clock looks equally precise from the page and from every worker realm
timer-grid-across-realmsperformance.now() does not hand a page the raw clock. Every engine coarsens it first — rounding the value onto a grid so that a page cannot…
Clearcote is a browser built for fingerprint coherence
It is a Chromium fork, maintained by the same people who wrote this reference. It ships as a compiled browser rather than as a stealth script injected into someone else's — which is a description of how it is built, and is not an argument about how it behaves on this check.
This audit takes no position on how Clearcote scores on Worker realms checks, on this one, or anywhere else. It has no baseline corpus of other people's fingerprints to rank you against and no vendor scoreboard — nearly every check is self-referential, asking one browser the same question through two independent APIs and reporting whether both answers can be true at once. It runs identically on any browser, including ours. Run it on yours and read the result yourself.
See the other checks in Worker realms — the family worker-uach-matches-page belongs to.