Angular Material button remove autofocus

After clicking or touching on a Material Design button it stays focused —> to resolve this, you need to add the following code: onclick="this.blur()"

<button mat-raised-button  onclick="this.blur()" (click)="onEdit()">Edit</button>

or in your case

<td mat-cell *matCellDef="let element">
    <button mat-icon-button type="button" onclick="this.blur()" (click)="downloadStuff(element)">
        <mat-icon mat-icon matTooltip="{{element.someId}}">picture_as_pdf</mat-icon>
    </button>
</td>