added bl_options = {"DEFAULT_CLOSED"}

space_view3d_3d_navigation.py

@@ -43,6 +43,7 @@ class VIEW3D_PT_3dnavigationPanel(bpy.types.Panel):
     bl_space_type = "VIEW_3D"
     bl_region_type = "TOOLS"
     bl_label = "3D Nav"
+    bl_options = {"DEFAULT_CLOSED"}
 
     def draw(self, context):
         layout = self.layout