Remove desktop hints since Openbox won't overwrite them, but they may be set from GDM or other sessions

data/xsession/openbox-gnome-session.in

@@ -7,6 +7,11 @@ if test -n "$1"; then
   exit
 fi
 
+# Clean up after GDM
+xprop -root -remove _NET_NUMBER_OF_DESKTOPS \
+      -remove _NET_DESKTOP_NAMES \
+      -remove _NET_CURRENT_DESKTOP 2> /dev/null
+
 VER=$(gnome-session --version 2>/dev/null | \
       sed -e 's/[^0-9.]*\([0-9.]\+\)/\1/')
 

data/xsession/openbox-kde-session.in

@@ -7,6 +7,11 @@ if test -n "$1"; then
   exit
 fi
 
+# Clean up after GDM
+xprop -root -remove _NET_NUMBER_OF_DESKTOPS \
+      -remove _NET_DESKTOP_NAMES \
+      -remove _NET_CURRENT_DESKTOP 2> /dev/null
+
 # Run KDE with Openbox as its window manager
 export KDEWM="@bindir@/openbox"
 exec startkde "$@"

data/xsession/openbox-session.in

@@ -7,6 +7,11 @@ if test -n "$1"; then
   exit
 fi
 
+# Clean up after GDM
+xprop -root -remove _NET_NUMBER_OF_DESKTOPS \
+      -remove _NET_DESKTOP_NAMES \
+      -remove _NET_CURRENT_DESKTOP 2> /dev/null
+
 AUTOSTART="${XDG_CONFIG_HOME:-"$HOME/.config"}/openbox/autostart.sh"
 GLOBALAUTOSTART="@configdir@/openbox/autostart.sh"