Hi,

if I'm not mistaken, the fop utility is not doing anything architecture
dependent. If that assertion is correct, please consider marking it as
Multi-Arch: foreign. I submitted a patch here:

https://salsa.debian.org/java-team/fop/-/merge_requests/1

Without this marking, source packages that build-depend on fop are not
able to satisfy their cross-build dependencies because they will try to
pull in the host-architecture fop which cannot work because fop is an
Architecture:all package. This affects at least 19 source packages in
Debian (I only checked the direct dependencies).

Thanks!

cheers, josch