FairEmail/app/src/main/res/layout/include_nav.xml

<?xml version="1.0" encoding="utf-8"?>
<androidx.constraintlayout.widget.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    android:layout_width="match_parent"
    android:layout_height="wrap_content">

    <androidx.recyclerview.widget.RecyclerView
        android:id="@+id/rvAccount"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:nestedScrollingEnabled="false"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toTopOf="parent" />

    <View
        android:id="@+id/vSeparatorAccount"
        android:layout_width="match_parent"
        android:layout_height="1dp"
        android:background="?attr/colorSeparator"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toBottomOf="@id/rvAccount" />

    <ImageButton
        android:id="@+id/ivExpanderUnified"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:background="?android:attr/selectableItemBackground"
        android:contentDescription="@string/title_legend_expander"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toBottomOf="@id/vSeparatorAccount"
        app:srcCompat="@drawable/expander" />

    <androidx.recyclerview.widget.RecyclerView
        android:id="@+id/rvUnified"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:nestedScrollingEnabled="false"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toBottomOf="@id/ivExpanderUnified" />

    <View
        android:id="@+id/vSeparatorUnified"
        android:layout_width="match_parent"
        android:layout_height="1dp"
        android:background="?attr/colorSeparator"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toBottomOf="@id/rvUnified" />

    <androidx.recyclerview.widget.RecyclerView
        android:id="@+id/rvFolder"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:nestedScrollingEnabled="false"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toBottomOf="@id/vSeparatorUnified" />

    <View
        android:id="@+id/vSeparatorFolder"
        android:layout_width="match_parent"
        android:layout_height="1dp"
        android:background="?attr/colorSeparator"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toBottomOf="@id/rvFolder" />

    <androidx.recyclerview.widget.RecyclerView
        android:id="@+id/rvMenu"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:nestedScrollingEnabled="false"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toBottomOf="@id/vSeparatorFolder" />

    <View
        android:id="@+id/vSeparatorMenu"
        android:layout_width="match_parent"
        android:layout_height="1dp"
        android:background="?attr/colorSeparator"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toBottomOf="@id/rvMenu" />

    <ImageButton
        android:id="@+id/ivExpanderExtra"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:background="?android:attr/selectableItemBackground"
        android:contentDescription="@string/title_legend_expander"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toBottomOf="@id/vSeparatorMenu"
        app:srcCompat="@drawable/expander" />

    <androidx.recyclerview.widget.RecyclerView
        android:id="@+id/rvMenuExtra"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:nestedScrollingEnabled="false"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toBottomOf="@id/ivExpanderExtra" />

    <androidx.constraintlayout.widget.Group
        android:id="@+id/grpUnified"
        android:layout_width="0dp"
        android:layout_height="0dp"
        app:constraint_referenced_ids="rvUnified,vSeparatorUnified" />
</androidx.constraintlayout.widget.ConstraintLayout>