Fixing Firefox Fonts
Firefox application fonts are rendered poorly in KDE. Firefox is a GTK application and as such does not utilise the QT widgets used in KDE. This produces bad fonts in the application window. To fix this in Debian install the gtk-qt-engine, which allows GTK apps to render correctly.
As root do:
aptitude install gtk-qt-engine
Restart Firefox and be amazed at the quality.
As a sidenote, I tend to use aptitude for my install, searches, deletes, updates and upgrades in Debian. You can use apt-get if you wish. Just replace the "aptitude" with "apt-get". I switched to aptitude some time back, as it takes care of any dependencies.
Thats about it.