The value given by the Mouse Wheel Axis is usually 1.0 or -1.0, depending on the direction. In HTML5 packages, this value varies based off the browser that is used.
On Firefox (56.0): 0.025 or -0.025
On Chrome (61.0.3163.100): 0.833333 or -0.833333
This also occurred in 4.16
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