PDFs no longer printing from Budgie 18.04LTS

Installed Budgie 18.04LTS on my mother’s (formerly Vista) PC a few years ago. Smooth install and she uses it frequently. Browses and prints whatever she wants. How many 86 year-olds can say they use Linux?

Suddenly it won’t print PDFs. It prints other docs and images, but three different PDF viewers only print blank pages. Accessed the PDF in question on my computer miles away, and it prints just fine. I tried reinstalling the printer driver, but no luck.

Any troubleshooting suggestions or do I need to travel several hundred miles and install a different OS? thanks

18.04 budgie is end of life now. 20.04 is recommended from a LTS point of view.

It does sound like a generic question that can be readily answered on ubuntuforums.org though so I would post a thread there where a wider ubuntu audience can advise further.