Do you have a printer connected to your device? You need a printer to have the printer in the list.

https://support.mozilla.org/en-US/kb/how-print-web-pages-firefox

Of course, Epson XP3150

Oh. That's strange. Is it for a specific webpage or for any page? Can you print with the printer from other applications, e.g. Libreoffice?

Thanks but after following all the suggestions on line I simply removed printer connection and reinstalled. Problem solved. Wish I had done that in the first place and saved a lot of time !

Thank you. I think it is always fun to solve the problem by yourself.