Dual-rumble is not DualSense haptics
PlayStation marketing and the Gamepad spec use similar words for different hardware. DualSense haptics are voice-coil actuators with a wide frequency range. Dual-rumble, in the browser, is gamepad.vibrationActuator.playEffect('dual-rumble', …) with a strong magnitude and a weak magnitude. That is the Xbox-style eccentric rotating mass pair, or a coarse approximation of it. If a tester promises “full DualSense haptics in Chrome,” it is overselling the API.
CTRLCHK checks for an actuator, pulses both magnitudes for half a second, and asks you what you felt: both motors, weak only, nothing, or skip. Your answer is stored on the report. It does not enter the weighted score. A pad with dead motors in Chrome should be described as “felt none.” A pad in Safari should be described as “unsupported.” Those are different sentences.
Where it works
Chromium on Windows and macOS is the reliable path. Some Linux builds expose the actuator; many do not. Firefox has historically stubbed or omitted it. If rumble is missing, the guided flow skips the step when you finish triggers. You will not sit on a locked Continue button because Mozilla declined a spec.
This page still starts a full health check, because a vibration-only toy that cannot see sticks is how people get tricked into thinking the rest of the pad is certified. For the rest of the measurements, stay on the guided steps or jump to drift, circularity, and snapback.