This an extension that I haven't released yet the reason for that is that I have had time to document how it work and there is also some code I want to refine.

The thing Silent Print does is that it makes it possible for webpages to print without the user needs to do anything. Now you probably think that that sound horrible, but it isn't. It only let sites that you whitelist print. So you can whitelist your internal website and let it print invoices and stuff like that. The extension makes it possible for webpages that set which printer to use and change settings. So with the extension everytime anyone are going to print something from your internal website you can make it look exactly the same. No need to train your staff which settings to use or which printer. A sample script could look something like this:

var sp = new SilentPrint();
sp.setString("printerName", "Canon A4");
if (sp.print())
  alert('Print successful');
else
  alert('There was some problem');

It also have some beta stuff in it. A part of the extension is the my first XPCOM-component that I programmed in C++. It is especially made for printing stuff directly to a receipt printer. You just set want string to print and they are sent directly to the printer. A sample script could look something like this:

var sp = new SilentPrint();
sp.setString("printerName", "Receipt printer");
sp.rawSetFont("FontA11");
sp.rawSetLine("This is a line which will be printed");
if (sp.rawPrint())
  alert('Print successful');
else
  alert('There was some problem');

Not sure when this extension will be release but if you want it right now please contact me and I can see what I can do.