How to hide my admin url when printing invoice from back end?

Hi.
I just noticed Firefox is printing my admin url on top of page when I print invoices from back end use laser printer. How to avoid this from zen cart side? Of course I can do it with Firefox settings. But we have staffs who are ignorant enough. It's hard to remind them about security risk involved about admin url exposure on paper trail.
http://mysite.net/admin/invoice.php?oID=29

Is it possible to print like bellow ? Is it possible to place invoice.php other than admin folder.
http://mysite.net/printinvoice/invoice.php?oID=29

gsmsalers:

Hi.
I just noticed Firefox is printing my admin url on top of page when I print invoices from back end use laser printer. How to avoid this from zen cart side? Of course I can do it with Firefox settings. But we have staffs who are ignorant enough. It's hard to remind them about security risk involved about admin url exposure on paper trail.
http://mysite.net/admin/invoice.php?oID=29

Is it possible to print like bellow ? Is it possible to place invoice.php other than admin folder.
http://mysite.net/printinvoice/invoice.php?oID=29

Here you go, it's part of the Zen Cart security recommendations too.
http://www.zen-cart.com/showthread.php?62172-removing-URL-from-invoices-when-printing