Não ter nenhum traço no utf-8 em mensagens de e-mail torna o conjunto de caracteres ilegível?

Question

O fato de não ter nenhum traço no utf-8 em cabeçalhos de mensagens de e-mail pode fazer com que clientes de e-mail exibam textos errados?

Subject: Newsletter
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Date: Mon, 29 Aug 2011 12:19:37 +0200
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Em oposição a:

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Estou perguntando, pois percebemos em alguns e-mails que, se há charset utf8 polish, os caracteres são ilegíveis.

    

Answer 1

A partir da entrada da Wikipedia em UTF-8 :

The official name is "UTF-8". All letters are upper-case, and the name is hyphenated. This spelling is used in all the documents relating to the encoding.
Alternatively, the name "utf-8" may be used by all standards conforming to the Internet Assigned Numbers Authority (IANA) list (which include CSS, HTML, XML, and HTTP headers),[15] as the declaration is case insensitive.

Other descriptions that omit the hyphen or replace it with a space, such as "utf8" or "UTF 8", are not accepted as correct by the governing standards. Despite this, most agents such as browsers can understand them, and so standards intended to describe existing practice (such as HTML5) may effectively require their recognition.

Então, basicamente, utf8 é tecnicamente incorreto (O Pior Tipo de Incorreto ™), e os programas não têm obrigação de aceitá-lo e Fazer a Coisa Certa (embora muitos possam fazê-lo com a bondade de seus corações). / p>