Shape is dropped onto ContainerShape and the container is auto-resized. When you press Ctrl + Z, the shape is removed, but the old size of the Container is not reverted. Expected : the container should return to its old size. When there is a nesting of containers and you drop a shape into in innermost container, Ctrl + Z will return the previos size of the container. Available in R3 2016 Official Release.
Please let me know when this problem will be fixed.
First case only happens putting a shape from Toolbox. Moving existing shape on diagram panel into container works well.