Dependency on unmaintained libxklavier

Hey,

I just received a Debian bug report about libxklavier going away at some point in the future: https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=1113815 and https://www.freedesktop.org/wiki/Software/LibXklavier/

I have no idea what options exist for migration but it looks a good idea to investigate it. The dependency looks optional at first sight but I'm unsure what we lose by disabling it.