Mac OS 8.5: Eject And Leave Behind No Longer Available
Using Mac OS 8.5, I went to eject the target floppy by holding down the Option key and selecting "Eject and Leave Behind" from the Special menu but the choice was not there.
Eject and Leave Behind has been removed from Mac OS 8.5. In fact, attempting to copy to any offline (greyed out) volume is no longer supported.
To duplicate floppies you can use Disk Copy which is available from Apple Software Updates.