Are the two json files from system_profiler -json SPFontsDataType > xx.json different ? (egrep '^ *"path"' xx.json | sort gives only the paths.) Also, what are the two macOS versions ?

@Tetsujin, nope, it stops -- versionitis. Thanks anyway

In case anyone is looking for 10.15, see install-xcode-on-macos-10-15-catalina on SO, and links there.

!! pbcopy puts the current line in the clipboard / pasteboard (and deletes it, u to put it back). You can then paste it wherever you like, x out characters ...

Thanks @Skeleton Bow, good idea -- Adobe\ Acrobat\ Reader\ DC.app for 10.10 prints better, not fat (must have its own print driver) but not as nice as in the browser -- mathml ? An overview of the whole process of rendering html with images, mathml / mathjax ... + screen or printer parameters would be useful.

@Skeleton Bow, pdfhost.io/v/IRlLIFk6E_Septic_equation1010downloadpdf.pdf and pdfhost.io/v/BAxcSPN7Y_Septic_equation1010printpdf.pdf. (But don't spend much time on it -- better things to do than chase old old bugs)

@Skeleton Bow, of course, where's an easy place to put them ? There are 2, from "download pdf": Septic_equation-10.10-download.pdf 673156 bytes, and "printable version" Septic_equation-10.10-print.pdf 488516)

NVIDIA GeForce GT 640M too ?

@Tetsujin, any idea why, whose bug ? Also I don't want to waste time and €€€ updating

Could you take a look at ugly-math-in-preview-of-wikipedia-pdfs please ? Maybe just versionitis (version disease)

Thanks. My real problem is that Wikipedia pages with math look good in html (firefox) but fat and ugly in preview "download pdf". (Macos 10.10 old fonts ?) pdffonts wikipediaxx.pdf lists them all as emb yes, don't understand; will post as a new question ... mañana.

How can one list a) the fonts embedded in a pdf, b) the fonts that preview loads from a local .../Fonts/... ? (a new question if you like). Thanks