v15.2 - Allow packages to set rectangular/non-rectangular display state

[Paolo F Cantoni]

As many of us now know, inserting a test in a shapescript for: if(hasproperty("rectanglenotation","?") will cause the context menu to have an item allowing the setting or unsetting of the rectangular notation property of an item on a diagram.  In the latest (v15.2) manifestation, this has moved to the "Paintbrush" widget.

However, for a package element on the diagram, even if the shapescript contains the "secret sauce", the context menu item doesn't appear.  This is in spite of the fact that if the state is altered by other means (such as a script) the shapescript will respond correctly.
Concistency, konsistency, consistensy! ^TM_{Uffe - after Paolo}

Can this be rectified, please?

Reported,
Paolo