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Open Terminal, type in:
defaults write com.apple.Safari IncludeDebugMenu 1
Restart Safari, use the debug menu to export your bookmarks.
In Terminal type in:
defaults write com.apple.Safari IncludeDebugMenu 0
Restart Safari again and it will be back to normal.
Open Firefox, import those bookmarks and away you go.
 
Thanks Guys, especially Duffman - the Safari Bookmark Exporter not only exported from Sarafi but imported into Firefox completely automatically.
 
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