diff --git a/core/res/res/values/config.xml b/core/res/res/values/config.xml
index 5d87f84332ae1..fa86b0efe3f4f 100644
--- a/core/res/res/values/config.xml
+++ b/core/res/res/values/config.xml
@@ -4848,9 +4848,8 @@
             - Option 3 is selected for R.integer.config_letterboxBackgroundType and blur requested
             but isn't supported on the device or both dark scrim alpha and blur radius aren't
             provided.
-        Defaults to black if not specified.
      -->
-    <color name="config_letterboxBackgroundColor">#000</color>
+    <color name="config_letterboxBackgroundColor">@android:color/system_neutral2_500</color>
 
     <!-- Horizonal position of a center of the letterboxed app window.
         0 corresponds to the left side of the screen and 1 to the right side. If given value < 0
diff --git a/services/core/java/com/android/server/wm/LetterboxConfiguration.java b/services/core/java/com/android/server/wm/LetterboxConfiguration.java
index eb7087cbc7222..34b834b3c6259 100644
--- a/services/core/java/com/android/server/wm/LetterboxConfiguration.java
+++ b/services/core/java/com/android/server/wm/LetterboxConfiguration.java
@@ -17,6 +17,7 @@
 package com.android.server.wm;
 
 import android.annotation.IntDef;
+import android.annotation.Nullable;
 import android.content.Context;
 import android.graphics.Color;
 
@@ -63,7 +64,10 @@ final class LetterboxConfiguration {
     private int mLetterboxActivityCornersRadius;
 
     // Color for {@link #LETTERBOX_BACKGROUND_SOLID_COLOR} letterbox background type.
-    private Color mLetterboxBackgroundColor;
+    @Nullable private Color mLetterboxBackgroundColorOverride;
+
+    // Color resource id for {@link #LETTERBOX_BACKGROUND_SOLID_COLOR} letterbox background type.
+    @Nullable private Integer mLetterboxBackgroundColorResourceIdOverride;
 
     @LetterboxBackgroundType
     private int mLetterboxBackgroundType;
@@ -81,20 +85,18 @@ final class LetterboxConfiguration {
     // side of the screen and 1.0 to the right side.
     private float mLetterboxHorizontalPositionMultiplier;
 
-    LetterboxConfiguration(Context context) {
-        mContext = context;
-        mFixedOrientationLetterboxAspectRatio = context.getResources().getFloat(
+    LetterboxConfiguration(Context systemUiContext) {
+        mContext = systemUiContext;
+        mFixedOrientationLetterboxAspectRatio = mContext.getResources().getFloat(
                 R.dimen.config_fixedOrientationLetterboxAspectRatio);
-        mLetterboxActivityCornersRadius = context.getResources().getInteger(
+        mLetterboxActivityCornersRadius = mContext.getResources().getInteger(
                 R.integer.config_letterboxActivityCornersRadius);
-        mLetterboxBackgroundColor = Color.valueOf(context.getResources().getColor(
-                R.color.config_letterboxBackgroundColor));
-        mLetterboxBackgroundType = readLetterboxBackgroundTypeFromConfig(context);
-        mLetterboxBackgroundWallpaperBlurRadius = context.getResources().getDimensionPixelSize(
+        mLetterboxBackgroundType = readLetterboxBackgroundTypeFromConfig(mContext);
+        mLetterboxBackgroundWallpaperBlurRadius = mContext.getResources().getDimensionPixelSize(
                 R.dimen.config_letterboxBackgroundWallpaperBlurRadius);
-        mLetterboxBackgroundWallpaperDarkScrimAlpha = context.getResources().getFloat(
+        mLetterboxBackgroundWallpaperDarkScrimAlpha = mContext.getResources().getFloat(
                 R.dimen.config_letterboxBackgroundWallaperDarkScrimAlpha);
-        mLetterboxHorizontalPositionMultiplier = context.getResources().getFloat(
+        mLetterboxHorizontalPositionMultiplier = mContext.getResources().getFloat(
                 R.dimen.config_letterboxHorizontalPositionMultiplier);
     }
 
@@ -158,12 +160,20 @@ final class LetterboxConfiguration {
     }
 
     /**
-     * Gets color of letterbox background which is  used when {@link
+     * Gets color of letterbox background which is used when {@link
      * #getLetterboxBackgroundType()} is {@link #LETTERBOX_BACKGROUND_SOLID_COLOR} or as
      * fallback for other backfround types.
      */
     Color getLetterboxBackgroundColor() {
-        return mLetterboxBackgroundColor;
+        if (mLetterboxBackgroundColorOverride != null) {
+            return mLetterboxBackgroundColorOverride;
+        }
+        int colorId = mLetterboxBackgroundColorResourceIdOverride != null
+                ? mLetterboxBackgroundColorResourceIdOverride
+                : R.color.config_letterboxBackgroundColor;
+        // Query color dynamically because material colors extracted from wallpaper are updated
+        // when wallpaper is changed.
+        return Color.valueOf(mContext.getResources().getColor(colorId));
     }
 
 
@@ -173,7 +183,16 @@ final class LetterboxConfiguration {
      * fallback for other backfround types.
      */
     void setLetterboxBackgroundColor(Color color) {
-        mLetterboxBackgroundColor = color;
+        mLetterboxBackgroundColorOverride = color;
+    }
+
+    /**
+     * Sets color ID of letterbox background which is used when {@link
+     * #getLetterboxBackgroundType()} is {@link #LETTERBOX_BACKGROUND_SOLID_COLOR} or as
+     * fallback for other backfround types.
+     */
+    void setLetterboxBackgroundColorResourceId(int colorId) {
+        mLetterboxBackgroundColorResourceIdOverride = colorId;
     }
 
     /**
@@ -181,8 +200,8 @@ final class LetterboxConfiguration {
      * com.android.internal.R.color.config_letterboxBackgroundColor}.
      */
     void resetLetterboxBackgroundColor() {
-        mLetterboxBackgroundColor = Color.valueOf(mContext.getResources().getColor(
-                com.android.internal.R.color.config_letterboxBackgroundColor));
+        mLetterboxBackgroundColorOverride = null;
+        mLetterboxBackgroundColorResourceIdOverride = null;
     }
 
     /**
diff --git a/services/core/java/com/android/server/wm/WindowManagerService.java b/services/core/java/com/android/server/wm/WindowManagerService.java
index 36809b374525e..3339269a6858a 100644
--- a/services/core/java/com/android/server/wm/WindowManagerService.java
+++ b/services/core/java/com/android/server/wm/WindowManagerService.java
@@ -1236,7 +1236,9 @@ public class WindowManagerService extends IWindowManager.Stub
         mAssistantOnTopOfDream = context.getResources().getBoolean(
                 com.android.internal.R.bool.config_assistantOnTopOfDream);
 
-        mLetterboxConfiguration = new LetterboxConfiguration(context);
+        mLetterboxConfiguration = new LetterboxConfiguration(
+                // Using SysUI context to have access to Material colors extracted from Wallpaper.
+                ActivityThread.currentActivityThread().getSystemUiContext());
 
         mInputManager = inputManager; // Must be before createDisplayContentLocked.
         mDisplayManagerInternal = LocalServices.getService(DisplayManagerInternal.class);
diff --git a/services/core/java/com/android/server/wm/WindowManagerShellCommand.java b/services/core/java/com/android/server/wm/WindowManagerShellCommand.java
index d59654949a27f..1d1cb7031148a 100644
--- a/services/core/java/com/android/server/wm/WindowManagerShellCommand.java
+++ b/services/core/java/com/android/server/wm/WindowManagerShellCommand.java
@@ -24,6 +24,7 @@ import static com.android.server.wm.LetterboxConfiguration.LETTERBOX_BACKGROUND_
 import static com.android.server.wm.LetterboxConfiguration.LETTERBOX_BACKGROUND_SOLID_COLOR;
 import static com.android.server.wm.LetterboxConfiguration.LETTERBOX_BACKGROUND_WALLPAPER;
 
+import android.content.res.Resources.NotFoundException;
 import android.graphics.Color;
 import android.graphics.Point;
 import android.graphics.Rect;
@@ -606,7 +607,7 @@ public class WindowManagerShellCommand extends ShellCommand {
             return -1;
         } catch (IllegalArgumentException  e) {
             getErrPrintWriter().println(
-                    "Error: 'reset' or aspect ratio should be provided as an argument " + e);
+                    "Error: aspect ratio should be provided as an argument " + e);
             return -1;
         }
         synchronized (mInternal.mGlobalLock) {
@@ -625,7 +626,7 @@ public class WindowManagerShellCommand extends ShellCommand {
             return -1;
         } catch (IllegalArgumentException  e) {
             getErrPrintWriter().println(
-                    "Error: 'reset' or corners radius should be provided as an argument " + e);
+                    "Error: corners radius should be provided as an argument " + e);
             return -1;
         }
         synchronized (mInternal.mGlobalLock) {
@@ -653,13 +654,13 @@ public class WindowManagerShellCommand extends ShellCommand {
                     break;
                 default:
                     getErrPrintWriter().println(
-                            "Error: 'reset', 'solid_color', 'app_color_background' or "
+                            "Error: 'solid_color', 'app_color_background' or "
                             + "'wallpaper' should be provided as an argument");
                     return -1;
             }
         } catch (IllegalArgumentException  e) {
             getErrPrintWriter().println(
-                    "Error: 'reset', 'solid_color', 'app_color_background' or "
+                    "Error: 'solid_color', 'app_color_background' or "
                         + "'wallpaper' should be provided as an argument" + e);
             return -1;
         }
@@ -669,6 +670,24 @@ public class WindowManagerShellCommand extends ShellCommand {
         return 0;
     }
 
+    private int runSetLetterboxBackgroundColorResource(PrintWriter pw) throws RemoteException {
+        final int colorId;
+        try {
+            String arg = getNextArgRequired();
+            colorId = mInternal.mContext.getResources()
+                    .getIdentifier(arg, "color", "com.android.internal");
+        } catch (NotFoundException e) {
+            getErrPrintWriter().println(
+                    "Error: color in '@android:color/resource_name' format should be provided as "
+                            + "an argument " + e);
+            return -1;
+        }
+        synchronized (mInternal.mGlobalLock) {
+            mLetterboxConfiguration.setLetterboxBackgroundColorResourceId(colorId);
+        }
+        return 0;
+    }
+
     private int runSetLetterboxBackgroundColor(PrintWriter pw) throws RemoteException {
         final Color color;
         try {
@@ -676,7 +695,7 @@ public class WindowManagerShellCommand extends ShellCommand {
             color = Color.valueOf(Color.parseColor(arg));
         } catch (IllegalArgumentException  e) {
             getErrPrintWriter().println(
-                    "Error: 'reset' or color in #RRGGBB format should be provided as "
+                    "Error: color in #RRGGBB format should be provided as "
                             + "an argument " + e);
             return -1;
         }
@@ -697,7 +716,7 @@ public class WindowManagerShellCommand extends ShellCommand {
             return -1;
         } catch (IllegalArgumentException  e) {
             getErrPrintWriter().println(
-                    "Error: 'reset' or blur radius should be provided as an argument " + e);
+                    "Error: blur radius should be provided as an argument " + e);
             return -1;
         }
         synchronized (mInternal.mGlobalLock) {
@@ -717,7 +736,7 @@ public class WindowManagerShellCommand extends ShellCommand {
             return -1;
         } catch (IllegalArgumentException  e) {
             getErrPrintWriter().println(
-                    "Error: 'reset' or alpha should be provided as an argument " + e);
+                    "Error: alpha should be provided as an argument " + e);
             return -1;
         }
         synchronized (mInternal.mGlobalLock) {
@@ -736,7 +755,7 @@ public class WindowManagerShellCommand extends ShellCommand {
             return -1;
         } catch (IllegalArgumentException  e) {
             getErrPrintWriter().println(
-                    "Error: 'reset' or multiplier should be provided as an argument " + e);
+                    "Error: multiplier should be provided as an argument " + e);
             return -1;
         }
         synchronized (mInternal.mGlobalLock) {
@@ -764,6 +783,9 @@ public class WindowManagerShellCommand extends ShellCommand {
                 case "--backgroundColor":
                     runSetLetterboxBackgroundColor(pw);
                     break;
+                case "--backgroundColorResource":
+                    runSetLetterboxBackgroundColorResource(pw);
+                    break;
                 case "--wallpaperBlurRadius":
                     runSetLetterboxBackgroundWallpaperBlurRadius(pw);
                     break;
@@ -1031,6 +1053,11 @@ public class WindowManagerShellCommand extends ShellCommand {
         pw.println("        is 'solid-color'. Use (set)get-letterbox-style to check and control");
         pw.println("        letterbox background type. See Color#parseColor for allowed color");
         pw.println("        formats (#RRGGBB and some colors by name, e.g. magenta or olive).");
+        pw.println("      --backgroundColorResource resource_name");
+        pw.println("        Color resource name of letterbox background which is used when");
+        pw.println("        background type is 'solid-color'. Use (set)get-letterbox-style to");
+        pw.println("        check and control background type. Parameter is a color resource");
+        pw.println("        name, for example, @android:color/system_accent2_50.");
         pw.println("      --wallpaperBlurRadius radius");
         pw.println("        Blur radius for 'wallpaper' letterbox background. If radius <= 0");
         pw.println("        both it and R.dimen.config_letterboxBackgroundWallpaperBlurRadius");