non-support of using surrogate pairs in CSS escapes [I18N-ACTION-90] [I18N-ISSUE-147]

Dear CSS WG,

I am writing to you on behalf of the I18N Core WG. During a recent teleconference [1] I was actioned with responding to a recent thread on your mailing list [2]. 

Here's a quote of much of that email:
WebKit browsers don’t support this syntax for characters outside the
BMP: ...

There seems to be another way to escape these characters, namely by
breaking them up in UTF-16 code units: `\d834\df06 `. All browsers
except Gecko (
seem to support this, even though this isn’t mentioned in the spec.

Should the spec be changed to reflect reality?

The Internationalization Core WG strongly opposes making such a change to the CSS spec. The Character Model [3] in requirement C045 requires that escape sequences be related to Unicode code point values, not to the code unit values used in some specific Unicode encoding (such as UTF-16). It is a barrier to content authors to have to convert escapes into UTF-16 surrogate pair sequences: it obfuscates the stylesheet, introduces additional processing complexity, and adds no value to support this syntax. Instead, user-agents should be encouraged to better meet the specification.

Regards (for I18N),




Addison Phillips
Globalization Architect (Lab126)
Chair (W3C I18N WG)

Internationalization is not a feature.
It is an architecture.

Received on Wednesday, 1 February 2012 05:00:36 UTC