I can't think of one. The pre tag was discussed already, see this thread: How 'bout a <pre> (and other stuff) warning?

In reply to Re^3: RecDescent Issue: using item hash with (?) repetition specifier by jethro
in thread RecDescent Issue: using item hash with (?) repetition specifier by Anonymous Monk

Title:
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and:  <code> code here </code>
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