Delete the line
and change the line own_window_type desktop to
When using own_window_type override windows are not under the control of the window manager. Hints are ignored.Windows are below and sticky.
When using own_window_type normal windows are under the control of the window manager and you must include another setting in the config for hints
own_window_type desktop causes problems when using nautilus to draw the desktop.(ie icons on the desktop)