Thanks for looking into this.
Just going to add, in case you wonder why it shouldn't be up to the
software that is mounting the ISO to sort out symbolic links and just
duplicate content, that neither Windows File Explorer nor 7-zip (both of
which can mount/extract ISO content) will list anything under the
'/firmware/' directory besides the 'dep11/' subdirectory and the
'Contents-firmware' file.
In short, a Windows user trying to use the most common ways of
extracting ISO content will be missing all the '*.deb' firmware files in
'/firmware/'. So this means that, unfortunately, the issue can't exactly
be dismissed as something that should be fixed at the ISO mounting level
rather than at the Debian ISO mastering level, at least for Windows users.
I guess one approach could be to have the Debian firmware detection and
loading software handle something like plain text files containing a
relative path when they use a specific extension (e.g. .deblink), in
order to perform the link resolution manually instead of relying on the
underlying file system...
Regards,
/Pete