I guess you could write a function that changes custom ID links into
external links prior to export, e.g., within
`org-export-before-parsing-hook'.
If I understand correctly, it would mean replacing "[[#link]]" with "[[./current-file.org::#link]]"? (I haven't yet verified if that #+INCLUDE-like syntax works for links too.)
Also, I am working on implementing this in an exporter backend. So what would be the canonical way to do that in ox-foo.el?
Thanks.
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