Attribute "target" exists, but can not be used for this element.
I found a nice work around that does not involve window.open, using jquery we can hack the attribute on 'after' the dom has loaded.
Now instead of target='_blank' you can just use class='target-blank', if the browser does not support javascript it will not open in a new window but the link will still work - and we have our valid xhtml.
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