Fix black missing window decorations in xfwm4

This is one of many problems i seem to have a problem discussing with anyone due to the growing rarity of Zaphod X configurations. In my configuration, i have three screens on different xorg servers (no xnest).  Using Mint14 and XFCE, when i log into my desktop environment, there are no window decorations (title bars, buttons, frames) drawn for the windows on displays :0.1 or :0.2. Only the first display (:0) has any window decorations; everything else is black.

Left: Everything is fine.  Right: Windeco's are missing

In my case, going to the Window Manager settings dialog and cycling between themes was sufficient to fix the issue.  If GTK settings are altered, the fix will need to be re-applied.  In order to simplify and automate this workaround, I  slapped a script together that uses xfconf-query to cycle to a different xfwm4 theme and back:

#!/bin/bash
# resets the xfwm4 window decoration theme
# this is a workaround to help enforce drawing on secondary $DISPLAYs

xfconf-query -c xfwm4 -p /general/theme -s Tgc
sleep 0.5
xfconf-query -c xfwm4 -p /general/theme -s Next

Stick this script wherever is convenient for your session startup needs.  I use it in a session template script, but there are more conventional places to put it.