angular-datatables: PagingType (full_numbers) and Buttons extension not working together

I’m submitting a…

[ ] Bug report  
[ ] Feature request
[ ] Documentation issue or request
[x] Question

Current behavior

When using the Buttons extension, it overrides the pagingType options (full_numbers) in the HTML view. Both options can’t be used at the same time. The pageLength option still works.

Expected behavior

I would like to be able to use the buttons extension while having the ability to chose the number of rows to display. Is it something possible ? Let me know if it’s a datatables.net thing.

Minimal reproduction of the problem with instructions

HTML:

<table datatable [dtOptions]="dtOptions" [dtTrigger]="dtTrigger" 
class="row-border hover responsive">
  <thead>
    <tr>
        <th> Series </th>
        <th *ngFor="let element of elements">{{element.symbol}}</th>
    </tr>
  </thead>
  <tbody>
    <tr *ngFor="let key of keys">
      <td>{{key}}</td>
      <td *ngFor="let cert of dataSourceCerts[key]">{{cert.precision === null ? '' : (cert.certifiedAvg | number: '1.' + cert.precision +'-'+ cert.precision)}}</td>
    </tr>
  </tbody>
</table>

Typescript:

dtOptions: any = {};
dtTrigger: Subject<any> = new Subject();
ngOnInit() {
    this.dtOptions = {
      pagingType: 'full_numbers',
      pageLength: 10,
      dom: 'Bfrtip',
      buttons: [
        'excel',
        'print'
      ]
    };
}
ngOnDestroy(): void {
    this.dtTrigger.unsubscribe();
}

Environment

- node version: 8.11.1
- angular version: 6.0.4
- angular-cli version: 6.0.8
- jquery version: 3.3.1
- datatables version: 1.10.16
- angular-datatables version: 6.0.0