The problem exists on Ikiwiki's wiki, but manifests itself differently, in that subpages are still displayed, so maybe that's the actual bug :)
Anyway, to reproduce, edit any page, view the page location options, preview, and some will disappear.
+
+> Yeah, this is a dark corner. :-) It'd be nice if preview did preserve the
+> lise, but it's complex to do so. So for now the bug is that it added
+> userdirs to the list, which I've fixed, so calling this [[done]]
+> --[[Joey]]