Run the check
Move across a marked surface with the mouse flat.
Lift slowly with a thin spacer while moving and note when the trail stops.
Repeat with the same surface and sensor setting for comparison.
Read the result
A repeatable stop point compares configurations but is not a calibrated millimeter reading.
Limits and next step
Browser coordinates contain OS scaling and no sensor-height data.
Repeat the check after changing one setting or connection. Keep a record of what changed before deciding whether the device needs service.