https://bugzilla.redhat.com/show_bug.cgi?id=1965684
--- Comment #5 from pk pimk1n@gmx.com --- Retested from live ISO of F32 KDE spin and confirmed issue present in Firefox and adding symlink to 11-lcdfilter-default.conf does resolve. This has freetype 2.10.1-2 & firefox 75.0-1.
F32 is when I first noticed it, not an issue in F31.
Debian 11 KDE has 11-lcdfilter-default.conf symlink by default and no font issue in Firefox, openSUSE Tumbleweed KDE appears to work a bit differently, but also not showing this issue.