diff --git a/res/values/themes.xml b/res/values/themes.xml
index 18cc40ed9c0..4fa0c9f7545 100644
--- a/res/values/themes.xml
+++ b/res/values/themes.xml
@@ -188,6 +188,7 @@
         <item name="android:windowTranslucentStatus">false</item>
         <item name="android:windowTranslucentNavigation">false</item>
         <item name="android:windowDrawsSystemBarBackgrounds">false</item>
+        <item name="android:background">@android:color/black</item>
 
         <!-- LockPatternView colors -->
         <item name="@*android:regularColor">@color/unlock_pattern_view_regular_color</item>