anchor.diff:  { stdenv, fetchurl, pkgconfig, gtk, pango, perl, python, zip, libIDL
   , libjpeg, libpng, zlib, cairo, dbus, dbus_glib, bzip2, xlibs
   , freetype, fontconfig, file, alsaLib, nspr, nss, libnotify
  -, yasm, mesa
  +, yasm, mesa, sqlite
   
   , # If you want the resulting program to call itself "Firefox" instead
     # of "Shiretoko" or whatever, enable this option.  However, those
  
positive.code:       "--with-system-nspr"
        # "--with-system-nss"
        # "--with-system-png" # <-- "--with-system-png won't work because the system's libpng doesn't have APNG support"
        # Disabled system Cairo for now because it causes gradients in tabs etc. to be missing.
        # "--enable-system-cairo"
        # Compiling with the Nixpkgs SQLite gives:
        # "configure: error: System SQLite library is not compiled with SQLITE_SECURE_DELETE."
        # "--enable-system-sqlite"
        "--disable-crashreporter"
        "--disable-tests"
        "--disable-necko-wifi" # maybe we want to enable this at some point
  
negative.code:     buildInputs =
        [ pkgconfig gtk perl zip libIDL libjpeg zlib cairo bzip2 python
          dbus dbus_glib pango freetype fontconfig alsaLib nspr libnotify
          xlibs.pixman yasm mesa sqlite
        ];
  
      propagatedBuildInputs = [xulrunner];
  