mathvariant attribute and isolated Arabic mathematical characters

Dear all,

Unicode contains some "ARABIC MATHEMATICAL" characters in the range
1EE00-1EE1F corresponding to the "isolated" forms in plane 0. The MathML
specification does not explicitly mention these characters and there is
no "isolated" mathvariant value. So it seems that they should just be
ignored for the mathvariant implementation (and this is indeed what
Gecko does). However:

1) In https://www.w3.org/TR/arabic-math/#N10951 it seems that the
initial intention was to make mathvariant="normal" force the isolated
form for Arabic characters.

2) The file unicode.xml from http://www.w3.org/TR/xml-entity-names/
contains some mapping <surrogate mathvariant="isolated">

Could you please clarify if there is some relation between the
mathvariant attribute and these isolated Arabic mathematical characters?

Thanks,

-- 
Frédéric Wang