nicht angemeldet
Habe eben in der FAQ des Validators die Antwort gefunden (http://validator.w3.org/docs/help.html#faq-linkandmeta):
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HTML is based on SGML and uses an SGML feature (called SHORTTAG) (note that this is not the case with XHTML).
With this feature enabled, the "/" in <link ... /> or <meta ... /> already closes the link (or meta) tag, and the ">" becomes some regular text, which is not allowed in the <head> element. Since </head><body> is optional in HTML (again, not in XHTML), it is silently inserted, thus head-only elements like meta and style as well as "</head>" and "<body>", which may appear only once, become false.
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Gibt also wohl keine Möglichkeit, mit Meta-Tags gleichzeitig HTML 4.01 und XHTML-kompatibel zu arbeiten.
Ciao!
Haefti