allow insert Measure, VBox, or HBox before a VBox or HBox

Inserting a Measure, VBox, or HBox before a *Measure* works fine, but if musescore won't let me insert a Measure, VBox, or HBox before a VBox or HBox.

Selecting a V/H Box and pressing insert button on keyboard or double clicking a V/H Box or Measure from palette, or dragging & dropping a V/H Box or Measure from palette onto the V/H Box I want to insert before all result in the V/H Box or Measure being appended to the end of my score.

But I want the V/H Boxes and Measures to be inserted before the V/H Box.

I am wondering if there is a deliberate reason why musescore won't let me do this. Can someone give me the goahead to try to implement?