[upofadown]

I don't think ancient HTML was complicated enough to have quirks.

[richardwhiuk]

Really? Looking at the source of that page:

IMG tags with unquoted SRC attributes, and unquoted ALIGN attribute

BASE tag with default attribute - tag is: <base="http://www.lysator.liu.se/pinball/expo/"> but should be <base href="http://www.lysator.liu.se/pinball/expo/">

UL tags with no LI tags