ShowEntryDetails shows the default PwDefs.HiddenPassword text even if there is no password field at all. Likewise of other hidden standard fields.
See attached patch file against v.2.09 to fix this.
This is intended. By not showing anything when the password field is empty, the next (then reasonable) step would be to show as many asterisks as the length of the password (otherwise users would be confused; why would an empty field be a special case?), and this of course would reveal the lengths of all passwords in the main window, i.e. decreasing security. So, I'm not going to change the current behavior.