diff --git a/spec/operators/shareReplay-spec.ts b/spec/operators/shareReplay-spec.ts
index 96a4c9e2c2..020209826e 100644
--- a/spec/operators/shareReplay-spec.ts
+++ b/spec/operators/shareReplay-spec.ts
@@ -3,7 +3,7 @@ import * as sinon from 'sinon';
 import { hot, cold, expectObservable, expectSubscriptions } from '../helpers/marble-testing';
 import { shareReplay, mergeMapTo, retry } from 'rxjs/operators';
 import { TestScheduler } from 'rxjs/testing';
-import { Observable, Operator, Observer, of } from 'rxjs';
+import { Observable, Operator, Observer, of, from } from 'rxjs';
 
 declare const rxTestScheduler: TestScheduler;
 
@@ -267,7 +267,15 @@ describe('shareReplay operator', () => {
   });
 
   it('should not skip values on a sync source', () => {
-    const a = cold(  '(abcd)');
+    const a = from(['a', 'b', 'c', 'd']);
+    // We would like for the previous line to read like this:
+    //
+    // const a = cold('(abcd|)');
+    //
+    // However, that would synchronously emit multiple values at frame 0,
+    // but it's not synchronous upon-subscription.
+    // TODO: revisit once https://github.com/ReactiveX/rxjs/issues/5523 is fixed
+
     const x = cold(  'x-------x');
     const expected = '(abcd)--d';