Enable two-finger scrolling in XFCE (horiz + vert)

By default, two-finger scrolling is enabled on XFCE on OSS11.4 when you have a Synaptics touchpad that has this feature...
But only vertical scrolling is enabled, to also get horizontal two-finger scrolling you have to add 2 lines to the following file (as root!):

/etc/X11/xorg.conf.d/50-synaptics.conf

The lines in bold do the magic!

Section "InputClass"
        Identifier "touchpad catchall"
        Driver "synaptics"
        MatchIsTouchpad "on"
        MatchDevicePath "/dev/input/event*"
        Option  "HorizScrollDelta"      "0"
        Option     "VertTwoFingerScroll"      "1"     # multitouch
        Option     "HorizTwoFingerScroll"     "1"     # multitouch
EndSection

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