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a held mouse button reported some pressure

Check id pointer-pressure-on-press

What an ordinary browser yields

Non-zero pressure while a mouse button is held; 0.5 on hardware with no pressure sensor. N/A for touch and pen, whose pressure comes from the digitiser (severity: warn).

What a detector infers

PointerEvent.pressure is not a range to model, it is a constant to check. The Pointer Events spec pins it for hardware with no pressure sensor: 0.5 whenever a button is active, and 0 only when none is. Measured against a PHYSICAL mouse on Chrome 150 - pointerdown with buttons 1 reported pressure exactly 0.5, and the matching pointerup reported 0, precisely as specified. Measured against SeleniumBase 4.51.5 driving the same page through CDP: 0 on the press. Input.dispatchMouseEvent takes an optional `force` parameter and reports zero pressure when it is omitted, which every wrapper measured so far omits. A pointerdown that claims a button is held while reporting no pressure at all is therefore not something a pointing device produces. This row is scored as ZERO-WHILE-HELD rather than NOT-EXACTLY-0.5, and the difference matters: a Force Touch trackpad still reports pointerType "mouse" and hardware could legitimately report 0.42, so demanding the constant would convict honest devices, while demanding merely that a held button produce some pressure cannot, because the spec forbids zero there. A driver can silence this row by passing force: 0.5, and that is the correct outcome rather than a defeat - the row asserts a property of the event, and an event that carries it honestly is not a complaint. PROVENANCE, because it is the point: this is the one row on the page whose baseline came from physical hardware before it was written. The neighbouring key-identity row was reasoned from a CDP control arm and got its justification wrong as a result - the control arm dispatched char events without a code, and the resulting empty value was mistaken for what browsers do. A control arm built from the same protocol as the thing under test is a second sample, not a baseline.

How to resolve it

Pass force: 0.5 to Input.dispatchMouseEvent on the press and 0 on the release, matching what a device with no pressure sensor reports. Nothing to fix for anyone using an actual mouse, trackpad or pen.

Nearby checks in Automation surface

See all 37 checks in Automation surface
Who builds this test

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 Automation surface 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 Automation surface — the family pointer-pressure-on-press belongs to.