I agree they do a good job, but I think a toast without undo could also work there. Apply the UI eagerly, toast success or failure. As it is, I assume on failure it becomes an 'X' and shows an error? I just dont generally like very short transitions like the spinner is currently. In general, coming from app land, I prefer a deferred loading spinner that only shows if the action takes X ms. So in the happy path of a fast action the user never sees the loading state.