mFlexID
U32 = 0 Index of the flex slot, 0, 1 or 2. Any other value reads 0, so the property has no effect.
An additive flex value with a two-component amount. The holder adds flex * mValue
to its base property, per component. FlexValueFloat describes
the slot reads.
U32 = 0 Index of the flex slot, 0, 1 or 2. Any other value reads 0, so the property has no effect.
Amount added per unit of flex value, a ValueVector2.