bug#4231: Need more reproduction information.

[Karl Fogel]

Thanks.  I think I'll need a concrete reproduction recipe here -- that
is, something with an actual remote filename in it.  I haven't used
remote files for 10 years or more (since the early days of ange-ftp),
and have no idea of what the syntax or setup is like now.  Having the
full reproduction recipe will save me a lot of time.