Downstream report: https://bugzilla.redhat.com/show_bug.cgi?id=1013562 Lots of Fedora users are seeing Thunar crash when ejecting removable media. Might be related to a glib2 change or something else, as it didn't happen at release time.
This is actually a gtk bug and has been fixed upstream in gtk3 and now also gtk2. https://bugzilla.gnome.org/show_bug.cgi?id=723366 You'll need Fedora to backport the fix... I thought we had a bug report somewhere for this already, but I guess not.
Closing since it's not a bug in Thunar or Xfce.