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That last one is for HTML5 . Unfortunately, in version and only works in Tapestry 5.2.5 and later versions. In earlier versions, Tapestry didn't support the HTML5 doctype directly (see TAP5-1040), but there's a partial work-around: just add the following to your page class (or your layout class, if you use one) instead of adding the doctype to your template (.tml) files:
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