I reported a bug at trac.filezilla :
“Enter on NumberPad crashes client (when changing a filename)”,
and Tim Kosse replied:
Unsupported third-party build
with custom, explicitly advised against modifications
to link against unsupported libraries.
I guess this is an Arch package, but afaik
they don’t like Manjaro users reporting problems on Arch forums.
Not asking you to do anything, just letting you know. 
Fortunately the bug is very minor.
When I first reported it I thought Fz always crashed after editing a filename,
but later discovered that it’s only when I hit Enter on the NumPad (which I usually do).