I notice that sl added a -c option, that is not documented in the
manpage shipped with debian.

However upstream now has a manpage on its own, and it does document that
flag.

Please consider switching or merging or do something with that :)

I support this wish because of the low quality German translation of the
current man page.

Translating it is waste of ressources.
It is also not clear where the translation comes from Upstream do not
provide translations.
It is obvious that the German man page was translated by a machine or a
none native speaker.

Kind