[EAI] mailto: escaping

[Shawn Steele <[e-mail]>]

I didn't see any discussion of my mailto: comments.

I think that it's good for the mailto: doc to provide escaping of the UTF-8 code points, however I also think that many clients will be quite liberal in what they allow.  (Safari & IE on Windows already seem to allow mailto:café(at)example.org and I don't see any reason to break that)

In other words in 2) I'd like to see the language:

"Applications MAY process UTF-8 encoded values in mailbox and hvalue directly even if they aren't percent-encoded."

Also it looks like hvalue SHOULD be percent encoded, but in the mailbox section it says "Percent-encoding can be used to denote non-ASCII characters" without any SHOULDs that I can see.

I'm happy for hvalue (and mailbox) to have SHOULD be percent-encoded for IRI [RFC3987] compatibility, though I note that humans typing mailto values directly aren't likely to do this.

4.1 also says "angle brackets...are mandatory", but doesn't use MUST language.  I'd like it to be SHOULD:

   Please note that if the left-hand side of the mail address contains
   non-ASCII characters, the less-than and greater-than sign (angle
   brackets, escaped as %3C and %3E) SHOULD be included.

(Why are <> necessary?)

I'd also like similar language if the angle brackets are missing

"Applications MAY process UTF-8 encoded mailbox values directly even if the RECOMMENDED angle brackets are not present"

I don't think it's realistic to expect current systems (Browsers, OS, etc.) to be more restrictive than they already are.  Specifically UTF-8 domain names tend to work fine with mailto in IDN aware systems, regardless of percent encoding or angle brackets.

Any comments this time? :)

-Shawn