Fonts

To have better fonts in Firefox, you need to disable anti-aliasing, and clear all font caches.

Do achieve this, run the following commands from a terminal:

Clear the cached fonts in your home directory

cd ~
rm -f .fonts.conf .fonts.cache-1 .fontconfig/*

Disable antialiasing

cd /etc/fonts/
sudo mv 10-antialias.conf disabled-10-antialias.conf 

Reconfigure the fonts

sudo dpkg-reconfigure fontconfig

Now, restart FIrefox and check if the fonts look better ...