When doing a copy & paste or drag & drop of a file between file systems the "target" windows shows a smaller filesize than the "source" window. Refreshing the "target" window (F5 or Ctrl+R) does not help. In a terminal window I can see the correct filesize. After closing all Thunar windows and opening the "target" window again shows the correct filesize.
However, I have also seen cases where the "target" file was really truncated.
Any comments will be appreciated.

This issue was also posted for Slackware on Linuxquestions.org - I am not allowed yet to post URLs ....