Here's a quick blog post to tell the world I'm now doing a French gender-neutral translation for Roundcube.
A while ago, someone wrote on the Riseup translation list to complain against
the current fr_FR translation. French is indeed a very gendered language and
it is common place in radical spaces to use gender-neutral terminologies.
So yeah, here it is: https://github.com/baldurmen/roundcube_fr_FEM
I haven't tested the UI integration yet, but I'll do that once the Riseup folks integrate it to their Roundcube instance.