1. Starting "xfprint4" 2. Click on the folder icon by "In File:" The window can't closed with [x] or "Cancel"-Button. Just with the parent window will the dialog closed.
That bug is not valid: The dialog is a modal, so the focus will remain in the file selector until the user chooses a file. The default theme in the wm doesn't show buttons on unfocused windows (just an anesthetic choice, if you don't liek that, just use another theme, there are morethan 70 to choose from) but you still can use the right mouse click on the title bar to display the menu and close the unfocused window. BTW I think the current behaviour is perfectly ocrrect, it doesn't make sense to close the main window before the file is selected.
Ahhh, all my apologizes! I see the problem ,this is indeed a perfectly valid bug!
Will be fixed in the next pre-release (RC1).