ubuntu-22.04.3-desktop-amd64/casper/filesystem/etc/fonts/conf.d

conf.d/README

Each file in this directory is a fontconfig configuration file.  Fontconfig
scans this directory, loading all files of the form [0-9][0-9]*.conf.
These files are normally installed in /usr/share/fontconfig/conf.avail
and then symlinked here, allowing them to be easily installed and then
enabled/disabled by adjusting the symlinks.

The files are loaded in numeric order, the structure of the configuration
has led to the following conventions in usage:

 Files begining with:	Contain:
 
 00 through 09		Font directories
 10 through 19		system rendering defaults (AA, etc)
 20 through 29		font rendering options
 30 through 39		family substitution
 40 through 49		generic identification, map family->generic
 50 through 59		alternate config file loading
 60 through 69		generic aliases, map generic->family
 70 through 79		select font (adjust which fonts are available)
 80 through 89		match target="scan" (modify scanned patterns)
 90 through 99		font synthesis