diff --git a/core/java/android/app/WindowConfiguration.java b/core/java/android/app/WindowConfiguration.java
index a486b9501e0c9..ec81ae3bc7c2b 100644
--- a/core/java/android/app/WindowConfiguration.java
+++ b/core/java/android/app/WindowConfiguration.java
@@ -20,11 +20,13 @@ import static android.app.ActivityThread.isSystem;
 import static android.app.WindowConfigurationProto.ACTIVITY_TYPE;
 import static android.app.WindowConfigurationProto.APP_BOUNDS;
 import static android.app.WindowConfigurationProto.BOUNDS;
+import static android.app.WindowConfigurationProto.MAX_BOUNDS;
 import static android.app.WindowConfigurationProto.WINDOWING_MODE;
 import static android.view.Surface.rotationToString;
 
 import android.annotation.IntDef;
 import android.annotation.NonNull;
+import android.annotation.Nullable;
 import android.annotation.TestApi;
 import android.compat.annotation.UnsupportedAppUsage;
 import android.content.res.Configuration;
@@ -35,8 +37,10 @@ import android.util.proto.ProtoInputStream;
 import android.util.proto.ProtoOutputStream;
 import android.util.proto.WireTypeMismatchException;
 import android.view.DisplayInfo;
+import android.view.WindowManager;
 
 import java.io.IOException;
+import java.util.Objects;
 
 /**
  * Class that contains windowing configuration/state for other objects that contain windows directly
@@ -63,6 +67,12 @@ public class WindowConfiguration implements Parcelable, Comparable<WindowConfigu
      */
     private Rect mAppBounds;
 
+    /**
+     * The maximum {@link Rect} bounds that an app can expect. It is used to report value of
+     * {@link WindowManager#getMaximumWindowMetrics()}.
+     */
+    private Rect mMaxBounds = new Rect();
+
     /**
      * The current rotation of this window container relative to the default
      * orientation of the display it is on (regardless of how deep in the hierarchy
@@ -179,26 +189,30 @@ public class WindowConfiguration implements Parcelable, Comparable<WindowConfigu
     /** Bit that indicates that the {@link #mAppBounds} changed.
      * @hide */
     public static final int WINDOW_CONFIG_APP_BOUNDS = 1 << 1;
+    /** Bit that indicates that the {@link #mMaxBounds} changed.
+     * @hide */
+    public static final int WINDOW_CONFIG_MAX_BOUNDS = 1 << 2;
     /** Bit that indicates that the {@link #mWindowingMode} changed.
      * @hide */
-    public static final int WINDOW_CONFIG_WINDOWING_MODE = 1 << 2;
+    public static final int WINDOW_CONFIG_WINDOWING_MODE = 1 << 3;
     /** Bit that indicates that the {@link #mActivityType} changed.
      * @hide */
-    public static final int WINDOW_CONFIG_ACTIVITY_TYPE = 1 << 3;
+    public static final int WINDOW_CONFIG_ACTIVITY_TYPE = 1 << 4;
     /** Bit that indicates that the {@link #mAlwaysOnTop} changed.
      * @hide */
-    public static final int WINDOW_CONFIG_ALWAYS_ON_TOP = 1 << 4;
+    public static final int WINDOW_CONFIG_ALWAYS_ON_TOP = 1 << 5;
     /** Bit that indicates that the {@link #mRotation} changed.
      * @hide */
-    public static final int WINDOW_CONFIG_ROTATION = 1 << 5;
+    public static final int WINDOW_CONFIG_ROTATION = 1 << 6;
     /** Bit that indicates that the {@link #mDisplayWindowingMode} changed.
      * @hide */
-    public static final int WINDOW_CONFIG_DISPLAY_WINDOWING_MODE = 1 << 6;
+    public static final int WINDOW_CONFIG_DISPLAY_WINDOWING_MODE = 1 << 7;
 
     /** @hide */
     @IntDef(flag = true, prefix = { "WINDOW_CONFIG_" }, value = {
             WINDOW_CONFIG_BOUNDS,
             WINDOW_CONFIG_APP_BOUNDS,
+            WINDOW_CONFIG_MAX_BOUNDS,
             WINDOW_CONFIG_WINDOWING_MODE,
             WINDOW_CONFIG_ACTIVITY_TYPE,
             WINDOW_CONFIG_ALWAYS_ON_TOP,
@@ -228,6 +242,7 @@ public class WindowConfiguration implements Parcelable, Comparable<WindowConfigu
     public void writeToParcel(Parcel dest, int flags) {
         dest.writeParcelable(mBounds, flags);
         dest.writeParcelable(mAppBounds, flags);
+        dest.writeParcelable(mMaxBounds, flags);
         dest.writeInt(mWindowingMode);
         dest.writeInt(mActivityType);
         dest.writeInt(mAlwaysOnTop);
@@ -238,6 +253,7 @@ public class WindowConfiguration implements Parcelable, Comparable<WindowConfigu
     private void readFromParcel(Parcel source) {
         mBounds = source.readParcelable(Rect.class.getClassLoader());
         mAppBounds = source.readParcelable(Rect.class.getClassLoader());
+        mMaxBounds = source.readParcelable(Rect.class.getClassLoader());
         mWindowingMode = source.readInt();
         mActivityType = source.readInt();
         mAlwaysOnTop = source.readInt();
@@ -290,7 +306,27 @@ public class WindowConfiguration implements Parcelable, Comparable<WindowConfigu
         setAppBounds(rect.left, rect.top, rect.right, rect.bottom);
     }
 
+    /**
+     * Sets the maximum bounds to the provided {@link Rect}.
+     * @param rect the new bounds value.
+     * @see #getMaxBounds()
+     * @hide
+     */
+    public void setMaxBounds(@Nullable Rect rect) {
+        if (rect == null) {
+            mMaxBounds.setEmpty();
+            return;
+        }
+        mMaxBounds.set(rect);
+    }
 
+    /**
+     * @see #setMaxBounds(Rect)
+     * @hide
+     */
+    public void setMaxBounds(int left, int top, int right, int bottom) {
+        mMaxBounds.set(left, top, right, bottom);
+    }
 
     /**
      * Sets whether this window should be always on top.
@@ -328,6 +364,14 @@ public class WindowConfiguration implements Parcelable, Comparable<WindowConfigu
         return mBounds;
     }
 
+    /**
+     * @see #setMaxBounds(Rect)
+     * @hide
+     */
+    public Rect getMaxBounds() {
+        return mMaxBounds;
+    }
+
     public int getRotation() {
         return mRotation;
     }
@@ -381,6 +425,7 @@ public class WindowConfiguration implements Parcelable, Comparable<WindowConfigu
     public void setTo(WindowConfiguration other) {
         setBounds(other.mBounds);
         setAppBounds(other.mAppBounds);
+        setMaxBounds(other.mMaxBounds);
         setWindowingMode(other.mWindowingMode);
         setActivityType(other.mActivityType);
         setAlwaysOnTop(other.mAlwaysOnTop);
@@ -398,6 +443,7 @@ public class WindowConfiguration implements Parcelable, Comparable<WindowConfigu
     public void setToDefaults() {
         setAppBounds(null);
         setBounds(null);
+        setMaxBounds(null);
         setWindowingMode(WINDOWING_MODE_UNDEFINED);
         setActivityType(ACTIVITY_TYPE_UNDEFINED);
         setAlwaysOnTop(ALWAYS_ON_TOP_UNDEFINED);
@@ -424,6 +470,10 @@ public class WindowConfiguration implements Parcelable, Comparable<WindowConfigu
             changed |= WINDOW_CONFIG_APP_BOUNDS;
             setAppBounds(delta.mAppBounds);
         }
+        if (!delta.mMaxBounds.isEmpty() && !delta.mMaxBounds.equals(mMaxBounds)) {
+            changed |= WINDOW_CONFIG_MAX_BOUNDS;
+            setMaxBounds(delta.mMaxBounds);
+        }
         if (delta.mWindowingMode != WINDOWING_MODE_UNDEFINED
                 && mWindowingMode != delta.mWindowingMode) {
             changed |= WINDOW_CONFIG_WINDOWING_MODE;
@@ -462,6 +512,9 @@ public class WindowConfiguration implements Parcelable, Comparable<WindowConfigu
         if ((mask & WINDOW_CONFIG_APP_BOUNDS) != 0) {
             setAppBounds(delta.mAppBounds);
         }
+        if ((mask & WINDOW_CONFIG_MAX_BOUNDS) != 0) {
+            setMaxBounds(delta.mMaxBounds);
+        }
         if ((mask & WINDOW_CONFIG_WINDOWING_MODE) != 0) {
             setWindowingMode(delta.mWindowingMode);
         }
@@ -504,6 +557,10 @@ public class WindowConfiguration implements Parcelable, Comparable<WindowConfigu
             changes |= WINDOW_CONFIG_APP_BOUNDS;
         }
 
+        if (!mMaxBounds.equals(other.mMaxBounds)) {
+            changes |= WINDOW_CONFIG_MAX_BOUNDS;
+        }
+
         if ((compareUndefined || other.mWindowingMode != WINDOWING_MODE_UNDEFINED)
                 && mWindowingMode != other.mWindowingMode) {
             changes |= WINDOW_CONFIG_WINDOWING_MODE;
@@ -550,6 +607,15 @@ public class WindowConfiguration implements Parcelable, Comparable<WindowConfigu
             if (n != 0) return n;
         }
 
+        n = mMaxBounds.left - that.mMaxBounds.left;
+        if (n != 0) return n;
+        n = mMaxBounds.top - that.mMaxBounds.top;
+        if (n != 0) return n;
+        n = mMaxBounds.right - that.mMaxBounds.right;
+        if (n != 0) return n;
+        n = mMaxBounds.bottom - that.mMaxBounds.bottom;
+        if (n != 0) return n;
+
         n = mBounds.left - that.mBounds.left;
         if (n != 0) return n;
         n = mBounds.top - that.mBounds.top;
@@ -589,11 +655,9 @@ public class WindowConfiguration implements Parcelable, Comparable<WindowConfigu
     @Override
     public int hashCode() {
         int result = 0;
-        if (mAppBounds != null) {
-            result = 31 * result + mAppBounds.hashCode();
-        }
-        result = 31 * result + mBounds.hashCode();
-
+        result = 31 * result + Objects.hashCode(mAppBounds);
+        result = 31 * result + Objects.hashCode(mBounds);
+        result = 31 * result + Objects.hashCode(mMaxBounds);
         result = 31 * result + mWindowingMode;
         result = 31 * result + mActivityType;
         result = 31 * result + mAlwaysOnTop;
@@ -607,6 +671,7 @@ public class WindowConfiguration implements Parcelable, Comparable<WindowConfigu
     public String toString() {
         return "{ mBounds=" + mBounds
                 + " mAppBounds=" + mAppBounds
+                + " mMaxBounds=" + mMaxBounds
                 + " mWindowingMode=" + windowingModeToString(mWindowingMode)
                 + " mDisplayWindowingMode=" + windowingModeToString(mDisplayWindowingMode)
                 + " mActivityType=" + activityTypeToString(mActivityType)
@@ -634,6 +699,7 @@ public class WindowConfiguration implements Parcelable, Comparable<WindowConfigu
         if (mBounds != null) {
             mBounds.dumpDebug(protoOutputStream, BOUNDS);
         }
+        mMaxBounds.dumpDebug(protoOutputStream, MAX_BOUNDS);
         protoOutputStream.end(token);
     }
 
@@ -659,6 +725,10 @@ public class WindowConfiguration implements Parcelable, Comparable<WindowConfigu
                         mBounds = new Rect();
                         mBounds.readFromProto(proto, BOUNDS);
                         break;
+                    case (int) MAX_BOUNDS:
+                        mMaxBounds = new Rect();
+                        mMaxBounds.readFromProto(proto, MAX_BOUNDS);
+                        break;
                     case (int) WINDOWING_MODE:
                         mWindowingMode = proto.readInt(WINDOWING_MODE);
                         break;
diff --git a/core/proto/android/app/window_configuration.proto b/core/proto/android/app/window_configuration.proto
index 18439da1a56fe..b158b31caa171 100644
--- a/core/proto/android/app/window_configuration.proto
+++ b/core/proto/android/app/window_configuration.proto
@@ -30,4 +30,5 @@ message WindowConfigurationProto {
     optional int32 windowing_mode = 2;
     optional int32 activity_type = 3;
     optional .android.graphics.RectProto bounds = 4;
+    optional .android.graphics.RectProto max_bounds = 5;
 }
diff --git a/services/tests/wmtests/src/com/android/server/wm/WindowConfigurationTests.java b/services/tests/wmtests/src/com/android/server/wm/WindowConfigurationTests.java
index c359fb1415d70..45cd6a200d019 100644
--- a/services/tests/wmtests/src/com/android/server/wm/WindowConfigurationTests.java
+++ b/services/tests/wmtests/src/com/android/server/wm/WindowConfigurationTests.java
@@ -27,6 +27,7 @@ import static android.app.WindowConfiguration.WINDOWING_MODE_UNDEFINED;
 import static android.app.WindowConfiguration.WINDOW_CONFIG_ALWAYS_ON_TOP;
 import static android.app.WindowConfiguration.WINDOW_CONFIG_APP_BOUNDS;
 import static android.app.WindowConfiguration.WINDOW_CONFIG_BOUNDS;
+import static android.app.WindowConfiguration.WINDOW_CONFIG_MAX_BOUNDS;
 import static android.app.WindowConfiguration.WINDOW_CONFIG_ROTATION;
 import static android.app.WindowConfiguration.WINDOW_CONFIG_WINDOWING_MODE;
 import static android.content.pm.ActivityInfo.CONFIG_WINDOW_CONFIGURATION;
@@ -78,11 +79,14 @@ public class WindowConfigurationTests extends WindowTestsBase {
         final WindowConfiguration winConfig3 = config3.windowConfiguration;
         final Configuration config4 = new Configuration();
         final WindowConfiguration winConfig4 = config4.windowConfiguration;
+        final Configuration config5 = new Configuration();
+        final WindowConfiguration winConfig5 = config5.windowConfiguration;
 
         winConfig1.setAppBounds(0, 1, 1, 0);
         winConfig2.setAppBounds(1, 2, 2, 1);
         winConfig3.setAppBounds(winConfig1.getAppBounds());
         winConfig4.setRotation(Surface.ROTATION_90);
+        winConfig5.setAppBounds(winConfig1.getAppBounds());
 
         assertEquals(CONFIG_WINDOW_CONFIGURATION, config1.diff(config2));
         assertEquals(0, config1.diffPublicOnly(config2));
@@ -104,6 +108,13 @@ public class WindowConfigurationTests extends WindowTestsBase {
         assertEquals(0, config1.diff(config3));
         assertEquals(0, config1.diffPublicOnly(config3));
         assertEquals(0, winConfig1.diff(winConfig3, false /* compareUndefined */));
+
+        winConfig1.setMaxBounds(1, 1, 1, 1);
+        winConfig5.setMaxBounds(2, 2, 2, 2);
+        assertEquals(WINDOW_CONFIG_MAX_BOUNDS,
+                winConfig1.diff(winConfig5, false /* compareUndefined */));
+        assertEquals(CONFIG_WINDOW_CONFIGURATION, config1.diff(config5));
+        assertEquals(0, config1.diffPublicOnly(config5));
     }
 
     /** Tests {@link android.app.WindowConfiguration#compareTo(WindowConfiguration)}. */
@@ -115,6 +126,7 @@ public class WindowConfigurationTests extends WindowTestsBase {
         final Configuration config1 = new Configuration();
         final WindowConfiguration winConfig1 = config1.windowConfiguration;
         winConfig1.setAppBounds(1, 2, 3, 4);
+        winConfig1.setMaxBounds(1, 2, 3, 4);
 
         final Configuration config2 = new Configuration(config1);
         final WindowConfiguration winConfig2 = config2.windowConfiguration;
@@ -150,6 +162,12 @@ public class WindowConfigurationTests extends WindowTestsBase {
         assertNotEquals(0, winConfig1.compareTo(winConfig2));
         winConfig2.setRotation(winConfig1.getRotation());
 
+        // Different max bounds
+        winConfig2.setMaxBounds(0, 2, 3, 4);
+        assertNotEquals(0, config1.compareTo(config2));
+        assertNotEquals(0, winConfig1.compareTo(winConfig2));
+        winConfig2.setMaxBounds(winConfig1.getMaxBounds());
+
         assertEquals(1, blankConfig.compareTo(config1));
         assertEquals(1, blankWinConfig.compareTo(winConfig1));
     }