2.1.1470 Part 1 Section 184.108.40.206, hMode (Height Mode)
For additional notes that apply to this portion of the standard, please see the notes for wMode, §220.127.116.11(a).
a. The standard states that edge is a valid value for the val attribute of hMode.
Office only saves a value of factor for the val attribute. Files opened with val equal to edge will be changed to factor on save and the val of sibling element h will be updated to reflect this mode change and correctly preserve the manual size.