Hello Org Mode people!

This is my first bug-report :)

I found a problem on org-odt-export-to-odt function.
The export fails with 'OpenDocument export failed: Buffer is read-only: #<killed buffer>'.

The problem happens on ox-odt, when the file OrgOdtStyles.xml
permissions are read-only (this is true especially for Guix and Nix
where all the "store" is readonly). The file gets copied to /tmp/ob-*/
directory, and is then modified. However, the file is assumed to be
read/write. When the file is not, the export fails. I've sent a one-line
patch (simply change permissions to the newly-copied file):

> (set-file-modes (concat org-odt-zip-dir "styles.xml") #o600)

to guix-patches (here in CC, I'm also forwarding my original patch
submission here), but I've been suggested to send the patch upstream.

What do you think? I can submit a proper patch if needed (but feel free
to patch it yourself)

I want to thank everybody for how wonderful Org Mode is :)

Nicolò