An UL with a margin-bottom has LIs that contain As with hover. In IE/Win the UL margin-bottom disappears and comes back when moving the mouse up and down on the As. The UL is wrapped in a box with hasLayout (which triggers the problem.)
No hasLayout on the wrapper, no problem (hasLayout on the UL fixes the problem as well, but makes the list markers to disappear.)
With padding on the wrapper instead of margin on the UL, no problem.
The problem can be reproduced without lists, just with divs. A necessary trigger seems to be the background color of the anchors parents.
Like the previous but without background color on the parents of the anchors (corresponding to the LIs in the UL case.)
A smaller test case IE7-/Win: disappearing bottom margin on hover. A similar case IE7-/Win: jumping float bottom margin.
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