I have just bought a HP printer....and I use Ubuntu on my Laptop. and the printer is not printing anything?
Well I have bought the hp as I am not able to easily print documents of my Ubuntu operating system and now not even the printer I bought is printing this is disheartening.
I'm sorry that you're printer isn't working properly, but unless it just doesn't work when you're printing with Firefox and it works with other printing software, you should ask HP for support.
This is not a Firefox problem, but rather with your system. Most likely your printer isn't installed in the system
Check this article on Ubuntu.com and see if it helps. https://help.ubuntu.com/10.04/printing/C/printing.html