Fix: Grease pencil conversion to new type not in menu

When legacy grease pencil objects were selected the conversion operator was not visible.

Pull Request: https://projects.blender.org/blender/blender/pulls/109094

scripts/startup/bl_ui/space_view3d.py

@@ -3065,8 +3065,8 @@ class VIEW3D_MT_object_convert(Menu):
     def draw(self, context):
         layout = self.layout
         ob = context.active_object
-
-        if ob and ob.type == 'GPENCIL' and context.gpencil_data:
+        
+        if ob and ob.type == 'GPENCIL' and context.gpencil_data and not context.preferences.experimental.use_grease_pencil_version3:
             layout.operator_enum("gpencil.convert", "type")
         else:
             layout.operator_enum("object.convert", "target")