Unit Testing with Jest & Angular 10: "Uncaught (in promise): Error: Not supported"

I cannot unit test a component that uses Quill as I am getting this error:

Uncaught (in promise): Error: Not supported Error: Not supported at QuillService.<anonymous> (projects/ngx-quill/src/lib/quill.service.ts:25:29)

I am configuring Quill like this in my spec.ts file:

import { QuillModule } from 'ngx-quill';
...
beforeEach(async(() => {
    TestBed.configureTestingModule({
      declarations: [ ... ],
      imports: [ ... ],
      providers: [QuillModule.forRoot().providers],
      schemas: [CUSTOM_ELEMENTS_SCHEMA]
    })
    .compileComponents();
    fixture = TestBed.createComponent(...);
    component = fixture.componentInstance;
    fixture.detectChanges();
 }));

I am not testing Quill elements; at this point, even a dummy test does not pass because of this error. If I comment out the fixture.detectChanges() line above, the test passes correctly.

Thank you for any suggestions!

[KillerCodeMonkey]

yes it looks fine.

i think maybe it has something todo with your jest config.

maybe you could identify the real cause. i would guess that jest can not handle the async import in the service.

[KillerCodeMonkey]

sounds like a missing polyfill for promises?

which version of angular and ngx-quill do you use?

my unit tests are running without any problem