As far as I know Century Schoolbook is a postscript type 1 font and no longer supported by Gimp. From memory comes with LibreOffice.
A post about it here: https://www.gimp-forum.net/Thread-some-f...g-properly and here: https://forums.linuxmint.com/viewtopic.php?t=330392
Edit: On the other hand I have Century Schoolbook L installed. Listed as a system font and that works ok. Don't know
A post about it here: https://www.gimp-forum.net/Thread-some-f...g-properly and here: https://forums.linuxmint.com/viewtopic.php?t=330392
Edit: On the other hand I have Century Schoolbook L installed. Listed as a system font and that works ok. Don't know