rxjs groupBy() / flatMap() / group.reduce() problem

uhoh.js

//
// yields a stream of objects.
//
observable.subscribe(x => console.log(x))


//
// returns:
// []
// []
// []
// ...
// []
observable.groupBy(x => x.navntype)
.flatMap(group => group.reduce((acc, curr) => [...acc, ...curr], []))
.subscribe(x => console.log(x))

all the objects in the observable has the 'navnetype' property.