Chrome Version       : 63.0.3239.84
OS Version: 6.1 (Windows 10, V1709 + KB4041994)

Other browsers tested:
  Add OK or FAIL after other browsers where you have tested this issue:
     Safari: n/a
    Firefox: OK
    IE/Edge: n/a

What steps will reproduce the problem?
1.define mousemove event
2.requestPointerLock
3.log event.movementX and event.movementY, move the mouse

What is the expected result?
no spikes values / correct movement values

What happens instead of that?

Sometimes there are spikes which are not corresponding to real mouse movement.

Please provide any additional information below. Attach a screenshot if
possible.

The problem appears only on my Window10 system, on all other systems and Firefox it will work fine. And I can't remember to see this behavior before KB4041994. Note: You have to move the mouse to get this spike values.

Currently the only workaround for me is this to prevent the spike values:

if(Math.abs(_e.movementX)<300&&Math.abs(_e.movementY)<300)localMouse.AddXY(_e.movementX,_e.movementY);

Regards
Meinolf

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