src/vs/base/common/observableImpl/logging.ts/ConsoleObservableLogger/handleDerivedCreated
class ConsoleObservableLogger:	handleDerivedCreated(derived: Derived<unknown>): void {
		const existingHandleChange = derived.handleChange;
		this.changedObservablesSets.set(derived, new Set());
		derived.handleChange = (observable, change) => {
			this.changedObservablesSets.get(derived)!.add(observable);
			return existingHandleChange.apply(derived, [observable, change]);
		};
	}