this "changing" could be adding, removing or simply touching.
if thunar is compiled with --enable-debug I get the following message spammed 16 times:
(xfdesktop:8754): thunar-vfs-CRITICAL **: thunar_vfs_monitor_remove: assertion `g_list_find (monitor->handles, handle) != NULL' failed
the segfault only happens with thunar compiled with --disable-debug, will attach a full backtrace
Created attachment 1402
*** Bug 4329 has been marked as a duplicate of this bug. ***
Should be fixed in xfdesktop rev 27912.