Alignment of Toolbar-Content in Android and Windows

On Android and Windows, the toolbar content positions vertically.

<ion-header> <ion-toolbar> <ion-title>Contacts</ion-title> <button start (click)="presentPopover($event)"> <ion-icon name="options"></ion-icon> </button> <button end (click)="onAddContact($event)"> <ion-icon name="add"></ion-icon> </button> </ion-toolbar> </ion-header>

I can not get why this is not working. Also, the start/end/left/right positioning does not work. It just does nothing.

Thanks!