Unifying E_Modifier and Extend in UAX 29 (i.e. the necessity of GB10)

[Richard Wordingham via Unicode]

On Mon, 1 Jan 2018 13:24:29 +0530
Manish Goregaokar via Unicode <unicode at unicode.org> wrote:

> <random non-emoji, skin tone modifier> sounds very much like a
> degenerate case to me.

Generally yes, but I'm not sure that they'd be inappropriate for
Egyptian hieroglyphs showing human beings.  The choice of determinative
can convey unpronounceable semantic information, though I'm not sure
that that can be as sensitive as skin colour.  However, in such a case
it would also be appropriate to give a skin tone modifier the property
Extend.

Richard.