The local voices come from the claimed OS's speech engine
Under a macOS, Linux or mobile claim, no local voice is named 'Microsoft …'; under a Windows claim with three or more local voices, at least one is. Edge's online Microsoft voices are remote and do not count; N/A when no voices arrive and on non-Chromium engines (severity: warn).
What a detector infers
Voices marked localService are the host's own speech engine, enumerated by the browser from the operating system, and their names say where they came from. Local voices named 'Microsoft …' are Windows' speech engine and exist nowhere else; macOS supplies its own named voices, and Linux whatever speech-dispatcher has installed. So a browser claiming macOS, Linux or Android that lists a local Microsoft voice has a voice list from a Windows machine.
In the audit's corpus, 108 of 111 non-Windows captures list no local Microsoft voice; the three that do — two macOS Chromium captures with four local Microsoft voices each and an Android capture with three — are the shape this row catches. The rule is also applied from the other side, because the corpus supports it: 185 of 186 Windows captures with three or more local voices include a Microsoft one, and the exception lists Google's network voices as local.
Edge is not a false positive: its online Microsoft voices are reported as remote, so the localService filter leaves them out. It differs from speech-voices-vs-platform, which asks whether a Windows or macOS claim has any voices at all.
How to resolve it
The local voices come from the machine's speech engine, which no browser setting changes. Present the OS the browser runs on; a voice list copied from a Windows machine carries Windows' speech engine with it.
Nearby checks in Environment & locale
- Exactly one voice is the default, and it is the first
voice-default-is-firstChromium assembles one voice list — the operating system's voices first, then extension voices such as Google's network voices — and marks… - Google's network voices arrive as Google's exact set
google-voices-exact-setBranded Google Chrome on Windows, macOS and Linux adds a set of network voices from a component extension whose manifest lists exactly 19 of… - Intl's default locale is a UI locale desktop Chrome ships
intl-is-a-chrome-ui-localeChrome's Intl default locale — what new Intl.DateTimeFormat().resolvedOptions().locale returns — is not the operating system's region. - The browser's own UI strings are in the language Intl resolves
validation-message-vs-intlThe messages a browser writes itself — 'Please fill in this field.' under an empty required input — come from the renderer's resource… - MediaCapabilities powerEfficient agrees with WebCodecs prefer-hardware
power-efficient-vs-webcodecsMediaCapabilities.decodingInfo() reports whether decoding a format would be power-efficient, and WebCodecs' VideoDecoder.isConfigSupported()… - A playback AudioContext buffers more than an interactive one
playback-hint-buffers-moreAn AudioContext created with latencyHint 'playback' asks for a larger buffer than one created with 'interactive', and Chrome honours the… - AudioContext latencies are values Chrome's audio stack can produce
audio-latency-render-stateTwo AudioContext latencies are produced by the audio stack at particular moments, and their values are constrained in ways a constant is… - A granted geolocation fix carries a real accuracy
geolocation-has-accuracyEvery position a real location provider returns comes with an accuracy: the radius, in metres, within which the true position probably lies.
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 Environment & locale 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 Environment & locale — the family local-voice-vendor-vs-os belongs to.