BookmarksPortlet CPD neglected to include portletDefinitionId and so is unusable for publishing new instances of the bookmarks portlet. Adding this hidden parameter fixes.

      <parameter modify="publish-only">
        <name>portletDefinitionId</name>
        <label>Portlet Definition ID (should be hidden)</label>
        <type base="string" input="text" display="hidden">
          <!-- length and maxlength for text field -->
          <length>80</length>
          <maxlength>255</maxlength>
        </type>
        <example>BookmarksPortlet.BookmarksPortlet</example>
        <defaultValue>BookmarksPortlet.BookmarksPortlet</defaultValue>
      </parameter>