When I call for a printing of a page in Firefox, my Epson NX420 will no longer allow plain paper as a media option in printer settings, but only photo and presentation papers; and it allows only the Best Photo option under Print Quality. In both cases, other options are grayed out. Gray Scale is also grayed out. Why have the grayed-out options become unavailable in Firefox (but not, e.g., in Chrome)? How can I restore them?