Ionic capacitor android cannot show notification icon

Hello,
i’m using ionic capacitor and i want to send push notifications using firebase. Everything is working fine, but on android the icon is always shown as a square instead of my icon. I have created a icon with transparent background with white foregroundcolor. I also added this line to my manifest:

    <meta-data android:name="com.google.firebase.messaging.default_notification_icon" android:resource="@drawable/ic_action_remove" />

Would be great if someone could help me out