[UA-discuss] [UA-EAI] Request for review: Report on Evaluation of Websites for Acceptance of E-mail Addresses, 2019

John R. Levine johnl at iecc.com
Fri Jul 12 20:20:10 UTC 2019

On Fri, 12 Jul 2019, Marc Blanchet wrote:
>> With respect to the HTML5 pattern for e-mail addresses, I have talked to 
>> people in WHATWG about it.  That pattern is correct for ASCII addresses and 
>> it's not going to change to an EAI pattern because that would lead to web 
>> sites with ASCII mail systems accepting addresses to which they can't send 
>> mail.  They would be open to adding a new "eaimail" input type that accepts 
>> EAI addresses, to allow an easy upgrade when sites have EAI capable back 
>> ends.
>> Nothing is going to happen in WHATWG until one of their large members says 
>> they'll implement it which hasn't happened.  I've made some inquiries and 
>> gotten polite responses, but I can't do much more since I have no funding.
> from https://w3c.github.io/test-results/html53/implementation-report.html, 
> done back in september, Firefox seems to support, while others were not 
> tested.

Ah, that is as we say a can of worms.

The actual HTML spec that major browser vendors implement is the WHATWG 
living standard.  W3C copies that spec verbatim into their own standard, 
except that they make some incompatible changes.  WHATWG has repeatedly 
asked W3C not to do that, but W3C persists.

One of those incompatible changes is e-mail addresses.  WHATWG has a 
recommended address validation pattern pattern which is a subset of the 
RFC5321/5322 spec that matches what real mail systems accept well.  W3C 
changed that to accept any UTF-8 which is wrong for many reasons.  One is 
that it's gratuitously incompatible, another is that it provides no way to 
distinguish between EAI and non-EAI back end mail systems, and a third is 
that real EAI mail systems are unlikely to accept all of the random mixes 
of scripts and punctuation that the W3C pattern allows.

The way people use the WHATWG pattern is that they cut and paste it into 
their javascript libraries and the browser just runs the javascript.  So 
long as everyone follows WHATWG it hardly matters what W3C does.  Before 
WHATWG will add an EAI pattern for programmers to use, it needs an eaimail 
input type to distinguish EAI and non-EAI mail backends, which needs 
browser and web server support.

John Levine, johnl at iecc.com, Primary Perpetrator of "The Internet for Dummies",
Please consider the environment before reading this e-mail. https://jl.ly

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