Whenever is selected one file and any number of directories whole Thunar crashes. File needs to be just only one... more files (same or different formats) works ok. Does not matter in what order its selected, only condition is just one file selected with any directory.
Looks like a bug in the translation, one of the plurals is not correct. http://git.xfce.org/xfce/thunar/tree/po/cs.po#n1290 Does this happen with thunar -q; LANG=C thunar;?
fixed in the current cs.po file
English seems to be fine, did not test the others.
Ok thank you Michal.
*** Bug 9642 has been marked as a duplicate of this bug. ***