Julien Cubizolles <j.cubizolles@free.fr> writes:

> Thanks for looking into it. It seems the completion-function is now
> being accessed but unfortunately something is still wrong. The error
> message is
>
> org-publish-projects: Wrong type argument: sequencep,
> jc-org-publish-rename-beamer-pdf

I forgot that :preparation-function could also be a single function.
Attached is the updated patch to test.

> If I'm to bisect, is it possible to reload all org-mode files without
> restarting emacs ? Would M-x org-mode be enough ?

See `org-reload'.

Regards,