2.1.189 Part 4 Section 220.127.116.11, customXml (Inline-Level Custom XML Element)
For additional notes that apply to this portion of the standard, please see the notes for oMath, §18.104.22.168(d) .
a. The standard allows ins, del, moveTo, and moveFrom to contain inline customXml.
Word will fail to load a file if ins, del, moveTo, or moveFrom contains inline customXml.
b. The standard states a specific set of parent elements that can contain inline customXml elements.
Word allows the following parent elements in addition to those already listed: deg, den, e, fName, lim, num, oMath, sub, and sup.
c. The standard allows any string for the uri attribute.
Word will not open a file if the uri attribute is not declared in an accompanying attachedSchema element.
d. The standard states that the element attribute can contain any string value.
Word only allows values conforming to the XML specification; a string conforming to the definition of xsd:NCName with a length of at most 255 characters.