LibreTube/app/src/main/res/layout/dialog_addtoplaylist.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:orientation="vertical">

    <TextView
        android:id="@+id/title"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_margin="10dp"
        android:gravity="center"
        android:text="@string/app_name"
        android:textSize="20sp" />

    <Spinner
        android:id="@+id/playlists_spinner"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_margin="8dp"
        android:padding="8dp" />

    <Button
        android:id="@+id/addToPlaylist"
        style="@style/CustomDialogButton"
        android:layout_marginEnd="16dp"
        android:text="@string/addToPlaylist" />

</LinearLayout>