Added to the HTML v3 spec? Netscape claims their extensions *are* the
HTML v3 spec.
"Netscape Navigator 1.1's new capabilities include:
Advanced layout capabilities using HTML 3.0 tables and graphical
backdrops. These capabilities allow more sophisticated page presentation,
including multiple text columns and flexible image placement." 
Netscape's table markups do not conform to the HTML v3 DTD. Nowhere in
the DTD does it indicate that the border attribute may take a value for
thickness, or anything else, for example. There are numerous other
attributes that are nowhere to be found in the HTML 3.0 DTD, not to
mention the "notorious" <center> and <font> tags.
"Netscape Navigator's new HTML tags that enable features like tables and
background images are based upon the HTML 3.0 proposal. Netscape
Communications Corporation is an active participant in all Web-related
standard bodies and is a charter Full Member of the W3 Consortium. Please
read our discussion of Netscape's commitment to open standards, if you're
interested in more information." 
Open standards must be documented, so that others may implement them
correctly. As a member of the W3 Consortium, Netscape must know that HTML
is documented using the SGML Document Type Definition. Where is the DTD
for the Netscape 1.1N tags?
I refer you to "The Myth of Netscape and HTML 3.0"  for the rest of
this line of discussion, and some more pointers to other points of view.
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