DocumentationBe careful when using lastValueFrom and firstValueFromIt’s better to use “Subscribe Arguments”Knowing which is triggered in combineLatestdistinctUntilChanged()toPromise to lastValueFrom or firstValueFromObservables4 types of subjectsSubject - Expected 1 arguments, but got 0.pipe()SubscriptioncombineLatestcombineLatestAll (old: combineAll)switchMap