Angular 7 scroll event does not fire

Try this...No need to do anything with html.

import { Component, OnInit, HostListener } from '@angular/core';

@HostListener('window:scroll', ['$event']) getScrollHeight(event) {
   console.log(window.pageYOffset, event);
}

The reason for this behaviour is that angular material blocks the scroll event.

I solved it like this:

  ngAfterViewInit(): void {

    const content = document.querySelector('.mat-dialog-container');
    const scroll$ = fromEvent(content, 'scroll').pipe(map(() => content));

    scroll$.subscribe(element => {
      // do whatever
    });
  }

Here is an alternative solution which works rather well.

In short:

ngOnInit() {
    // Add an event listener to window
    // Window can be defined in the pollyfiles.ts as: 
    // if (window) {
    //    (window as any).global = window;
    // }
    window.addEventListener('scroll', this.scroll, true); //third parameter
}

ngOnDestroy() {
    window.removeEventListener('scroll', this.scroll, true);
}

scroll = (event: any): void => {
  // Here scroll is a variable holding the anonymous function 
  // this allows scroll to be assigned to the event during onInit
  // and removed onDestroy
  // To see what changed:
  const number = event.srcElement.scrollTop;
  console.log(event);
  console.log('I am scrolling ' + number);
};