session-android/res/drawable/conversation_list_item_unread_background_dark.xml

<?xml version="1.0" encoding="utf-8"?>
<selector xmlns:android="http://schemas.android.com/apk/res/android">
    <item android:drawable="@color/textsecure_primary_alpha33" android:state_selected="true" />
    <item android:drawable="@color/textsecure_primary_alpha33" android:state_pressed="true" />
    <item android:drawable="@color/conversation_list_item_background_unread_dark" />
</selector>