Quelle  activity_whatsnew.xml

<?xml version="1.0" encoding="utf-8"?>
<FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:id="@+id/root_view"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:fillViewport="true"
    android:background="?android:attr/colorBackground">

    <ImageView
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:scaleType="centerCrop"
        android:importantForAccessibility="no"
        android:alpha="0.6"
        android:src="?attr/whatsnew_wallpaper_drawable" />

    <LinearLayout
        android:id="@+id/content_container"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:orientation="vertical">

        <ScrollView
            android:id="@+id/scroll_container"
            android:layout_width="match_parent"
            android:layout_height="0dp"
            android:layout_weight="1.0"
            android:background="@android:color/transparent">

            <LinearLayout
                android:id="@+id/linearLayout"
                android:layout_width="match_parent"
                android:layout_height="wrap_content"
                android:orientation="vertical"
                android:paddingBottom="16dp"
                android:paddingLeft="18dp"
                android:paddingRight="18dp"
                android:paddingTop="16dp">

                <TextView
                    style="@style/Threema.TextAppearance.Title"
                    android:id="@+id/whatsnew_title"
                    android:layout_width="wrap_content"
                    android:layout_height="wrap_content"
                    android:layout_marginTop="16dp"
                    android:text="@string/whatsnew_title" />

                <ch.threema.app.emojis.EmojiTextView
                    style="@style/Threema.TextAppearance.BodyLarge"
                    android:id="@+id/whatsnew_body"
                    android:layout_width="match_parent"
                    android:layout_height="wrap_content"
                    android:layout_marginTop="16dp"
                    android:text="@string/whatsnew_headline" />

            </LinearLayout>

        </ScrollView>

        <LinearLayout
            android:id="@+id/button_layout"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:layout_marginBottom="16dp"
            android:layout_marginLeft="16dp"
            android:layout_marginRight="16dp"
            android:layout_marginTop="16dp"
            android:orientation="vertical">

            <com.google.android.material.button.MaterialButton
                style="@style/Threema.MaterialButton.Action"
                android:id="@+id/next_text"
                android:layout_gravity="center_horizontal"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:text="@string/ok" />

        </LinearLayout>

    </LinearLayout>

</FrameLayout>