Thanks, I replaced org-cycle/org-global-cycle with outline-cycle/outline-cycle-buffer, and then the outlining works.

On Tue, 6 Feb 2024 at 18:56, Ihor Radchenko <yantar92@posteo.net> wrote:
Daniel Clemente <n142857@gmail.com> writes:

> I also see the warnings. In my case it's because I'm using outline-minor
> mode in an elisp file. I'm not sure it's supported, but it worked years
> ago: ...

It is not supported by Org mode.
The modern outline mode has `outline-cycle'.

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Ihor Radchenko // yantar92,
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