Several attributes for paypal and GooglePlus were

问题:

Since 2007, we have used a local DTD to add a tag-pair and to define several attributes for PayPlal and google++. This is the local DTD...

<!ELEMENT havindex EMPTY>
<!ATTLIST havindex id CDATA #REQUIRED>
<!ENTITY % head.misc "(script|style|meta|link|object|isindex|havindex)*">
<!ENTITY % html.transitional PUBLIC
  "-//W3C//DTD XHTML 1.0 Transitional//EN"
  "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">

<!-- =========== 3 div attributes for googleplus share button ====== -->
<!ATTLIST div data-action       CDATA #IMPLIED>
<!ATTLIST div data-annotation   CDATA #IMPLIED>
<!ATTLIST div data-height       CDATA #IMPLIED>
<!ATTLIST div data-id           CDATA #IMPLIED>
<!-- =========== 2 script attributes for paypal support ========== -->
<!ATTLIST script data-pp-pubid          CDATA #IMPLIED>
<!ATTLIST script data-pp-placementtype  CDATA #IMPLIED>
%html.transitional;

... We recently converted the site to https (not sure that has anything to do with it, but just as an aside) and all of a sudden, it seems that the local DTD breaks the W3C validation - it fails immediately on the DTD. When I use a standard DTD, of course, the new tag and attributes are seen as validation errors. Any thoughts on how to use the local dtd or to define the attributes, at least?