[BR] Clipboard support on macOS and Org 9.7

[Juergen Fenn <jfenn@gmx.net>]

Dear all,

over at the Org mode mailinglist, Ihor and Visuwesh asked me to post a
bug report to emacs-devel about how Emacs handles the macOS clipboard. I
ran into troubles with a new feature that was introduced with Org 9.7
for attaching images to Org documents from the clipboard. We found out
that this does not work as expected under macOS. Please see our thread
starting at:

https://lists.gnu.org/archive/html/emacs-orgmode/2024-06/msg00014.html

I am sorry it took me a moment to respond to their request because (1)
in the meanwhile I had to upgrade from macOS Ventura to Sonoma and and
re-compile Emacs, and (2) there were some more unexpected technical and
real-life matters. So, here we go.

You might like to know that upgrading to Sonoma meant that I had to
re-compile my Emacs 29.3 because the one I had built under Ventura would
not run any more on the new platform. I managed to re-compile Emacs from
the 29.3 tarball I had used on Ventura, but I realised that I cannot
compile Emacs under Sonoma with gnutls. Although the latest gnutls is
installed on my machine (I even re-installed gnutls over Homebrew) and
though this posed no problem under Ventura, I had to use =./configure
--with-gnutls=ifavailable=. Perhaps there were some changes to the Apple
Command Line Tools, too, that I re-installed for Sonoma. I can install
new packages with package.el, but Emacs now keeps telling me that
=Package tls is deprecated=.

Anyway, I have tested the clipboard bug with Org 9.7.4 on GNU Emacs 29.3
(build 1, aarch64-apple-darwin23.5.0, NS appkit-2487.60 Version 14.5
(Build 23F79)) of 2024-06-09. Here is what I can reproduce:

- Open the file manager Finder and select a local jpg file.
- Press Command-c to copy the file to the clipboard.
- Switch to an Org buffer in Emacs.
- M-x yank-media.

It turns out that any file, regardless of its real format, gets attached
with a TIFF file ending.

M-x yank-media-type yields:

(1/3) Yank type:
clipboard:image/tiff
clipboard:STRING
clipboard:text/plain

Ihor found out that MIME type support in macOS indeed is incomplete:

https://lists.gnu.org/archive/html/emacs-orgmode/2024-06/msg00063.html

So, you might like to have a look into this.

My observations were confirmed by Christopher, another user on macOS, I
have included in CC.

Many thanks in advance.

Regards,
Jürgen.