I have been using the same method of creating Mathematica notebooks and saving them as PDF for over a decade. For some reason the PDF files are completely mangled when created on Linux.
There is a cache folder, and I did delete it. I also ran it under a different user.
Yes, Mathematica is proprietary. It’s been on Linux for 3 decades. I used to only use the Linux build. I was primarily on Windows for the past decade. Since I now have some money to buy computers and Windows 11 was exceedingly offensive to a free mind, I am now back on S.u.S.E.
Mathematica 14.0->14.1 was a major change in file structure and packaging. Each version has its own fonts directory in its installation tree. I’ve had trouble with Mathematica fonts in the past. Really don’t want to go there again. The fonts are determined by the stylesheets; which are very kludgy. The thing is, the problem exists in both versions, which I don’t believe overlap.
Mathematica is ancient technology. I’m guessing there is still K&R C in the source code. It’s a beast, but I rely on it more than any other software package. It has a lot in common with Emacs; good and bad.
It looks like there were some libc++ updates just before this problem emerged. Unfortunately, I did a lot of fiddling with the installation while troubleshooting a sound problem, so there were lost of packages removed and installed around that time.