Hello, I'm long Linux user (not exclusively). For about year I use Debian, as I learned that communit based software is important. I currently use Buster.
For long time problem for me was fonts hinting. I'm not sure if it is optimal, but for me selecting TrueType fonts in dpkg-reconfigure fontconfig-config makes correct font hinting, both in Gnome Desktop and Chromium browser. Firefox is however lacking. Currently Debian uses Firefox ESR. Firefox from Buster has copy of freetype library in modules/freetype2 dir. This is freetype 2.9 version . As stated here https://www.freetype.org/ version 2.10.1 correct TrueType hinting. Current Firefox from Mozilla already uses this most current freetype version. Does SID Firefox version helps with font rendering ? Best regards, Marek Mosiewicz