Building the list of system fonts is time consuming and is therefore cached.
This, in turn, means that changes to the system fonts (i.e. installing new
fonts), will not propagate to systemfonts. The solution is to reset the
cache, which will result in the next call to e.g. match_fonts() will
trigger a rebuild of the cache.
Examples
all_fonts <- system_fonts()
##-- Install a new font on the system --##
all_fonts_new <- system_fonts()
## all_fonts_new will be equal to all_fonts
reset_font_cache()
all_fonts_new <- system_fonts()
## all_fonts_new will now contain the new font