RFC 2646:The Text/Plain Format Parameter
RFC-Ref

HTML


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... media types, such as Text/Enriched [RICH] and Text/HTML [HTML] have suffered from a lack of backwards compatibility ...


... media types, such as Text/Enriched [RICH] and Text/HTML [HTML] have suffered from a lack of backwards compatibility ...
... line breaks be doubled, with resulting user unhappiness when viewed as Text/Plain. Text/HTML requires even more alteration of text, with a corresponding increase in user complaints. ...



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