Remove statement that all elements with overflow:hidden in ua style s…

…heet establish a viewport - it's not true.

master/styling.html

@@ -1156,9 +1156,7 @@ <h2 id='UAStyleSheet'>User agent style sheet</h2>
 clipping path</a> to be established at the bounds of the <a
 href="coords.html#ViewportSpace">initial viewport</a>.
 Furthermore, it will cause new clipping paths to be established
-at the bounds of the listed elements, all of which are <a
-href="coords.html#ElementsThatEstablishViewports">elements that
-establish a new viewport</a>. (Refer to the description of
+at the bounds of the listed elements (refer to the description of
 SVG's use of the <a>'overflow'</a> property for more
 information.)</p>