Training loss graph is updated when "discretize output" is selected or deselected

The graph visualizing the training loss is updated every time the "discretize output" box is selected or deselected, please see attached screen recording. Because no step is actually performed this is assumed to be a bug.

https://user-images.githubusercontent.com/5433242/227735348-754e36d2-727e-45f8-add5-f9591a4fe497.mov