GdkWindowlower

Lowers window to the bottom of the Z-order (stacking order), so that other windows with the same parent window appear above window. This is true whether or not the other windows are visible.

If window is a toplevel, the window manager may choose to deny the request to move the window in the Z-order, gdk_window_lower() only requests the restack, does not guarantee it.

Note that gdk_window_show() raises the window again, so don’t call this function before gdk_window_show(). (Try gdk_window_show_unraised().).