The closest thing is probably the `pandoc.utils.references`
function (added in pandoc 2.17). It gives you access to the
structured reference entries. Theoretically one could write a
custom citation handler by using that function and filtering
`Cite` elements; it might or might not be worth the effort in your
case.
Yeah, I'm making heavy use of that already for my filtering. It works fine for single citations, but I don't want to just totally swallow the existing citation in case it's part of a Cite that has other citations, though. This is what I mean about somehow filtering during citeproc so I could directly replace the emitted elements that form the footnote -- if I could do that I could wrap them in a span, change with greater confidence, etc.
(Sorry for the double-message to Alfred, but accidentally sent this only to him at first.)