I found the endless list of foreign fonts to be annoying, so I tried deleting them. Looking online it seemed that it was "ok" to go into
/usr/share/fonts, and hack away.
After I did this I discovered that the font menus in applications such as Libre Writer were still listing the fonts. When I chose them (say, any of the "noto" ones), I'd get the regular default font.....none of the glyphs were the foreign ones that were there previously.
So I tried these two things:
--> fc-cache -r
--> fc-cache -fv
and neither worked to remove those entries.
Is there a cache of entries someplace that needs to be built every time the
/usr/share/fontsdirectory is altered?