As the title suggests, when you open more than one tab in the same thunar window and then you try to move the files by dragging and dropping them through tabs, the files are moved but thunar crashes immediately. On my Linux box with latest XFCE it is 100% reproducible.
I can confirm that the problem now sometimes disappears but still exists. I am trying to find a way how to instigate the crash on a reproducible way.
Already being worked on in https://bugzilla.xfce.org/show_bug.cgi?id=12264. *** This bug has been marked as a duplicate of bug 12264 ***