Subject: How do I permanently get rid of the "Mirrored from ... by HTTrack ..."
messages?
The faq says "Use the footer option (-%F, or see the WinHTTrack options)".  

First of all, I don't see anywhere to edit the options.  There are several
menu items under "Preferences", but none allow you to actually edit them. 
Only save and load.

If you star to download a website, there IS an option to edit preferences at
that point.  I didn't see anything like "WinHTTrack options".  I did find a
footer and removed it.  It made no difference.