Signal-Android/app/src/main/res/layout/preference_username.xml

<?xml version="1.0" encoding="utf-8"?>
<FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    android:background="?attr/selectableItemBackground"
    android:layout_width="match_parent"
    android:layout_height="wrap_content">

    <androidx.appcompat.widget.AppCompatTextView
        android:layout_width="match_parent"
        android:layout_height="56dp"
        android:layout_marginStart="8dp"
        android:layout_marginTop="8dp"
        android:layout_marginEnd="15dp"
        android:layout_marginBottom="8dp"
        android:background="@drawable/preference_username_background"
        android:drawablePadding="18dp"
        android:gravity="center_vertical"
        android:paddingStart="18dp"
        android:paddingEnd="18dp"
        android:text="@string/preferences_setup_a_username"
        android:textAppearance="@style/Signal.Text.Body"
        app:drawableStartCompat="@drawable/ic_at_24"
        app:drawableTint="?colorAccent" />
</FrameLayout>