Comment 7 for bug 523917

Ah, is it the following part in /etc/fonts/conf.avail/29-language-selector-ja-jp.conf?

 <match target="font">
  <test name="lang" compare="contains">
   <string>ja</string>
  </test>
  <test name="pixelsize" compare="less_eq">
   <double>18</double>
  </test>
  <edit name="hintstyle" mode="assign">
   <const>hintnone</const>
  </edit>
 </match>