Angular 9 never calls HammerGestureConfig.buildHammer

After update to Angular 9 it does not work to use Hammer.js anymore. We have extended the Angular HammerGestureConfig like the following.:

import {HammerGestureConfig} from '@angular/platform-browser';
import {Injectable} from '@angular/core';

@Injectable({providedIn: 'root'})
export class HammerConfig extends HammerGestureConfig {

  overrides = <any>{
    'pan': {
      direction: Hammer.DIRECTION_ALL,
      threshold: 5
    } // override default settings
  };

  buildHammer(element) {
    const recognizers = [];
    if (element.hasAttribute('data-hammer-pan')) {
      recognizers.push([Hammer.Pan]);
    }
    if (element.hasAttribute('data-hammer-pan-x')) {
      recognizers.push([Hammer.Pan, {direction: Hammer.DIRECTION_HORIZONTAL}]);
    }
    if (element.hasAttribute('data-hammer-tap')) {
      recognizers.push([Hammer.Tap]);
    }
    if (element.hasAttribute('data-hammer-pinch')) {
      recognizers.push([Hammer.Pinch]);
    }
    if (element.hasAttribute('data-hammer-rotate')) {
      recognizers.push([Hammer.Rotate]);
    }
    if (element.hasAttribute('data-hammer-press')) {
      recognizers.push([Hammer.Press]);
    }
    if (element.hasAttribute('data-hammer-swipe')) {
      recognizers.push([Hammer.Swipe]);
    }
    const hammer = new Hammer.Manager(element, {
      recognizers: recognizers,
      touchAction: 'auto'
    });
    return hammer;
  }
}

The HammerConfig is added to the app module.:

  providers: [
    {
      provide: HAMMER_GESTURE_CONFIG,
      useClass: HammerConfig
    }
  ],

As far as I understand the method buildHammer should be called, but it is never called.

What could be the problem?

The HammerModule needs to be imported to the Angular app module.

  imports: [
    ...
    HammerModule
  ],
  providers: [
    {
      provide: HAMMER_GESTURE_CONFIG,
      useClass: HammerConfig
    },
    ...
  ],
  ...

ivy: make Hammer support tree-shakable. Previously, in Ivy applications, Hammer providers were included by default. With this commit, apps that want Hammer support must import HammerModule in their root module. (#32203) (de8ebbd)

https://github.com/angular/angular/blob/9.0.0/CHANGELOG.md