anchor.diff:  
       buildInputs =
         [ pkgconfig gtk perl zip libIDL libjpeg zlib cairo bzip2 python
  -        dbus dbus_glib pango freetype fontconfig alsaLib nspr libnotify
  +        dbus dbus_glib pango freetype fontconfig alsaLib nspr nss libnotify
           xlibs.pixman yasm mesa sqlite file unzip pysqlite
         ];
   
  
positive.code:       [ pkgconfig gtk perl zip libIDL libjpeg libpng zlib cairo bzip2
          python dbus dbus_glib pango freetype fontconfig xlibs.libXi
          xlibs.libX11 xlibs.libXrender xlibs.libXft xlibs.libXt file
          alsaLib nspr libnotify xlibs.pixman yasm mesa
          xlibs.libXScrnSaver xlibs.scrnsaverproto pysqlite
          xlibs.libXext xlibs.xextproto sqlite unzip makeWrapper
        ];
  
negative.code:         # Fall back to this url for versions not available at releases.mozilla.org.
          "ftp://ftp.mozilla.org/pub/mozilla.org/firefox/releases/${firefoxVersion}/source/firefox-${firefoxVersion}.source.tar.bz2"
      ];
      sha1 = "6a3a965c165ceda8c5ba038e9fe0136fbd1690ff";
    };
  
    commonConfigureFlags =
  