The Inspector's node highlight doesn't update when you edit CSS and end up changing a node's position on the page.
<rdar://problem/5732855>
Is this still an issue?
The patch in bug 21000 will fix this on the Mac.
Landed in r37046 for Mac. Now tracking this bug for Windows.
I can't reproduce this on Mac. Is this relevant anymore that highlights are implemented with InspectorOverlay?