[css-display-3] Tables are also an exception to normal box parentage. #3158

Author: fantasai

css-display-3/Overview.bs

@@ -86,9 +86,12 @@ Introduction</h2>
 	<a>Boxes</a> are often referred to by their 'display' type--
 	e.g. a <a>box</a> generated by an element with ''display: block'' is called a “block box” or just a “block”.
 	The <dfn export for=CSS>parent box</dfn> of an element’s <a>principal box</a>
-	is (except in the case of ''run-in'' or the generation of intervening <a>anonymous boxes</a>)
+	is, in general,
 	the <a>principal box</a> of its nearest ancestor element
-	that generates a <a>box</a>.
+	that generates a <a>box</a>;
+	there are exceptions for ''run-in'' boxes,
+	display types that generate multiple boxes (such as tables),
+	and intervening <a>anonymous boxes</a>.
 
 	A <a>box</a> is assigned the same styles as its generating [=CSS/element=], unless otherwise indicated.
 	In general, <a>inherited properties</a> are assigned to the <a>principal box</a>,