anchor.diff:  , freetype, fontconfig, file, alsaLib, nspr, nss, libnotify
   , yasm, mesa, sqlite, unzip, makeWrapper, pysqlite
   , hunspell, libevent, libstartup_notification, libvpx
  -, cairo, gst_all_1, icu, libpng, jemalloc
  +, cairo, gstreamer, gst_plugins_base, icu, libpng, jemalloc
   , enableGTK3 ? false
   , debugBuild ? false
   , # If you want the resulting program to call itself "Firefox" instead
  
positive.code:       xlibs.libXScrnSaver xlibs.scrnsaverproto pysqlite
        xlibs.libXext xlibs.xextproto sqlite unzip makeWrapper
        hunspell libevent libstartup_notification libvpx cairo
        gst_all_1.gstreamer gst_all_1.gst-plugins-base icu libpng
        jemalloc
      ]
      ++ lib.optional enableGTK3 gtk3;
  
negative.code:       "--enable-system-pixman"
        "--enable-system-sqlite"
        "--enable-system-cairo"
        "--enable-gstreamer"
        "--enable-startup-notification"
        "--enable-content-sandbox"            # available since 26.0, but not much info available
        "--disable-content-sandbox-reporter"  # keeping disabled for now
  