[css3-text] grapheme clusters across element boundary

There seems to be endless trouble if we consider corner cases involving
grapheme clusters across element boundary, i.e., for example, the
following case is not, and might forever not be, implemented interoperably:

data:text/html,t<u>&%23x308;</u><s>est</s> (where &#308; is U+0308
COMBINING DIAERESIS)

I suggest we explicitly mark this kind of situation as undefined in the
spec near the definition of a grapheme cluster, as I believe this is
better than saying nothing at all with regard to this.

Perhaps CSS Text beyond level 3 (or CSS Fonts?) should consider
addressing use case like coloring the combining mark separately form the
base character[1] although I wonder whether standardizing this behavior
might hard competition in the space of font systems.

[1] https://www.w3.org/Bugs/Public/show_bug.cgi?id=13502#c11

Cheers,
Kenny

Received on Saturday, 14 January 2012 17:54:02 UTC