Displaying drive letter in tab label is useful. However when label is copied to clipboard, the letter is copied too.
That is sometimes undesired.
Additional option "Do not copy drive letter to clipboard" would allow for both: having more informative labels and not having undesired (L:)etter in clipboard.
P.S.
This would be converse of current Firefox behaviour. FF displays "resource.dopus.com/viewforum.php?f=3" in address field, but copies "http://resource.dopus.com/viewforum.php?f=3" to clipboard.