Printing pages from Firefox shows badly pixellated and almost unreadable text for all except quite large size fonts. First uploaded image shows the first part of what I get if I print to PDF my own web page at http://www.zen224037.zen.co.uk/ Both printing to PDF and printing to a real printer show the same problem. Firefox displays this web page (and others) correctly. The second uploaded image shows what I get if I use Spectacle to take a screenshot of the page as correctly displayed by Firefox. Other applications can print correctly. The third uploaded image shows what I get if I open the source code of my web page with a text editor (kate) and ask it to print that to PDF. This problem seems to have appeared since I switched my graphics driver from "nouveau", which was causing my display to lock up, to the NVIDIA driver obtained from the openSUSE repository at https://download.nvidia.com/opensuse/leap/15.5 I tried clearing the startup cache as recommended on the Troubleshooting page, changing the size of Firefox's default font. and changing the default font to Adobe Helvetica. None of these helped.