Overfilter - shadow doesn't appear in Firefox

[Iain]

I recently downloaded a Vertical Plain Text Menu. Everything works fine except the drop-shadow when viewed in Firefox which doesn't appear at all. Is this a known bug?

[John]

It's not a bug - it's a Microsoft-ism. The filters (outfilter= and overfilter=) are IE-specific. That's the only place they will work.