Standardizing on IDNA 2003 in the URL Standard

Anne van Kesteren annevk at
Wed Aug 21 17:45:51 CEST 2013

On Wed, Aug 21, 2013 at 4:01 PM, Mark Davis ☕ <mark at> wrote:
> I agree with that, and it is the scenario envisioned for TR46. That is, once
> all (significant) registries move to IDNA2008, then then clients can impose
> stricter controls on the characters, excluding the characters that are
> disallowed in IDNA2008. Because the registries will have moved, the number
> of failing URLs would be acceptable.

I doubt that would be true for subdomains. E.g. I know people using
http://☺ as domain (forgot whether that particular code
point is excluded, but you get the idea).

It's also not true for URLs in resources that depend on the mapping to
happen. Especially for uppercase/lowercase I would expect that to be
fairly common. And in URLs in resources should remain
locale-insensitive. That they depend on encodings to some extent is
bad enough.


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