Nodejs: 17.2.0
npm: 8.2.0

Al ejecutar el comando npm start obtenemos el siguiente mensaje de error:

node_modules/rxjs/Subject.d.ts:24:5 - error TS2416: Property 'lift' in type 'Subject' is not assignable to the same proper
ty in base type 'Observable'.
  Type '(operator: Operator) => Observable' is not assignable to type '(operator: Operator) => Observabl
e'.
    Type 'Observable' is not assignable to type 'Observable'.
      Type 'T' is not assignable to type 'R'.
        'R' could be instantiated with an arbitrary type which could be unrelated to 'T'.

24     lift(operator: Operator): Observable;

Para solucionar el problema tenemos que instalar una version actualizada de rxjs

npm install --save rxjs@^5.4.2

java | Angular | rxjs

npm start, Observable(T) is not assignable to Observable(R)