MacOS info for all books

I propose to discuss this and decide on a solution for all the guides and
all the writers, via the list and/or the documentation team weekly meeting.

*If* macOS customisation is critical then please give more consideration to
coding it in the documents. It won't end there, scripting guides could be
customised for preferred programming language.

https://listarchives.libreoffice.org/global/documentation/2022/msg00006.html

If we add a control variable that hides or show sections/paragraphs
depending on the OS, documents will go into a very complex and fragile
management scheme where mistakes (e.g. deletion of a controlled
paragraph) are easily introduced and unnoticed. Debugging a long
document like our guides will be unpleasant at best.

Technically speaking, LibreOffice has all tools for document management
(version control, fields, track-changes...) but our team must get used
to and it is also a entry barrier for newcomers.

The Help has a control scheme (<switch>, <switchinline>) for macOS where
Ctrl key is changed to Command key and the menu "Tools-Option" is
changed to "LibreOffice - Preferences". Those are 99.99% of all
differences in Help between OS versions.

Regards