$ diff /usr/etc/xdg/xfce4/xfconf/xfce-perchannel-xml/xfce4-keyboard-shortcuts.xml{.orig,}
75c75
<       <property name="&lt;Super&gt;Tab" type="string" value="switch_window_key"/>
---
>       <property name="&lt;Super&gt;Tab" type="empty"/>
$