Here's what I ran:
install.packages("extrafont")
library(extrafont)
font_import()
Then it asked if I still wanted to proceed since it would take awhile
y
Then it seemed to run through all the font names, not finding any, with these comments for each font it was looking for:
C:\Windows\Fonts\ZWAdobeF.TTF : No FontName. Skipping.
Finally, it finished with these lines:
Found FontName for 0 fonts.
Scanning afm files in C:/Users/Lisa/Documents/R/win-library/4.1/extrafontdb/metrics
There were 50 or more warnings (use warnings() to see the first 50)
I went ahead and ran this:
> fonts()
NULL