Should race have a special case for synchronous observables?

Potential Bug Report

Current Behavior If a race observable is constructed with at least one synchronous observable, the order of events is confusing.

1. (Optionally) Subscribe to asynchronous observables that come before the first synchronous observable.
2. Subscribe to the first synchronous observable.
3. Copy the output from the synchronous observable.
4. Subscribe and immediately unsubscribe from all other observables.

Step 4 could be ommitted in my opinion. If this is intended behavior, maybe put a note about it in the documentation?

Reproduction https://stackblitz.com/edit/rxjs-ec1mwd

import { race, EMPTY } from 'rxjs';
import { create } from 'rxjs-spy';
import { tag } from 'rxjs-spy/operators';
import { delay, map } from 'rxjs/operators';

create().log(/.*/);
const source = race(
  EMPTY.pipe(delay(100), tag("e0")),
  EMPTY.pipe(tag("e1")),
  EMPTY.pipe(delay(100), tag("e2")),
  EMPTY.pipe(delay(100), tag("e3")),
).pipe(
  tag("output"),
)

source.subscribe();

Tag = output; notification = subscribe; matching /.*/
== Step 1
Tag = e0; notification = subscribe; matching /.*/
== Step 2
Tag = e1; notification = subscribe; matching /.*/
Tag = e1; notification = complete; matching /.*/
== Step 3
Tag = output; notification = complete; matching /.*/
Tag = output; notification = unsubscribe; matching /.*/
Tag = e0; notification = unsubscribe; matching /.*/
Tag = e1; notification = unsubscribe; matching /.*/
== Step 4
Tag = e2; notification = subscribe; matching /.*/
Tag = e2; notification = unsubscribe; matching /.*/
Tag = e3; notification = subscribe; matching /.*/
Tag = e3; notification = unsubscribe; matching /.*/

[mhverbakel]

Absolutely fine with me. Close it once you created the new one.

[cartant]

Closed in favour of #4808