I noticed the "Save" and "Save as" options are now disabled when there are no changes to save.
In my opinion, this should not be the case for the "Save as" option, it should always be available. One use case might be that the user wants to save the model under a different filename to have a backup or to use the current model as the starting point for a new model.
In my opinion, this should not be the case for the "Save as" option, it should always be available. One use case might be that the user wants to save the model under a different filename to have a backup or to use the current model as the starting point for a new model.