Multicasting and Reference Counting code examples in the docs don't typecheck

[jfhector]

Describe the bug

The following code example is used on the Overview / Subject page under Multicasting and under Reference Counting:

import { from, Subject, multicast } from 'rxjs';

const source = from([1, 2, 3]);
const subject = new Subject();
const multicasted = source.pipe(multicast(subject));

// These are, under the hood, `subject.subscribe({...})`:
multicasted.subscribe({
  next: v => console.log(`observerA: ${v}`),
});
multicasted.subscribe({
  next: v => console.log(`observerB: ${v}`),
});

// This is, under the hood, `source.subscribe(subject)`:
multicasted.connect();

But if I paste that in a TypeScript file, I get this TypeScript error:

Property 'connect' does not exist on type 'Observable<unknown>'.ts(2339)

(The issue reported by TypeScript seems to because .pipe returns an Observable, not a Subject. I believe that that behaviour is undocumented. I only found out after hours of struggling: a more helpful answer on that issue and not blocking comments there would help a lot please).

I'm aware that multicast has been deprecated. But refactoring using the migration guide does not solve the type error.

Expected behavior

The code example type checks.

Reproduction code

See above

Reproduction URL

No response

Version

7.5.6

Environment

No response

Additional context

No response