Do we want Perl in the Platform?
Perl is nowhere to be found in org.freedesktop.Platform//1.6, it's in the Sdk, because so much stuff depends on it for building.
However it is in org.freedesktop.Platform//unstable.
$ du -sh ~/.local/share/flatpak/runtime/org.freedesktop.Platform/x86_64/unstable/active/files/lib/perl5/
50M /home/mathieu/.local/share/flatpak/runtime/org.freedesktop.Platform/x86_64/unstable/active/files/lib/perl5/
This seems like a nice win if we decide to remove it, it's about 8% of the total size of the Platform.