Hi,
On my Debian testing machine, I installed fbreader 0.99.6 via guix. Running FBReader segfaults about 60% of the time on start up. If it makes it to a running program, it seems to run just fine. It is kind of usable in that I can just keep starting it until it works.
I asked on IRC where to report this. A user advised me to email this address.
Thanks,
James