MacIE does not follow the forward compatible parsing rules correctly. It should ignore selectors it cannot understand. This document contains the following stylesheet:
.test>.subhead { color: green; }
This is a CSS2 stylesheet saying that any element with
class="subhead" that is a child of
an element with class="test should be green.
The following paragraph has class="subhead"
but it is not a child of an element with class="test.
MacIE incorrectly makes it green:
This paragraph should not be green.