diff --git a/core/java/android/app/Activity.java b/core/java/android/app/Activity.java
index a0d0b30e65f79..5bc0647159a3b 100644
--- a/core/java/android/app/Activity.java
+++ b/core/java/android/app/Activity.java
@@ -944,6 +944,10 @@ public class Activity extends ContextThemeWrapper
     /** @hide */
     boolean mEnterAnimationComplete;
 
+    /** Track last dispatched multi-window and PiP mode to client, internal debug purpose **/
+    private Boolean mLastDispatchedIsInMultiWindowMode;
+    private Boolean mLastDispatchedIsInPictureInPictureMode;
+
     private static native String getDlWarning();
 
     /** Return the intent that started this activity. */
@@ -6999,6 +7003,10 @@ public class Activity extends ContextThemeWrapper
                 writer.print(mResumed); writer.print(" mStopped=");
                 writer.print(mStopped); writer.print(" mFinished=");
                 writer.println(mFinished);
+        writer.print(innerPrefix); writer.print("mLastDispatchedIsInMultiWindowMode=");
+                writer.print(mLastDispatchedIsInMultiWindowMode);
+                writer.print(" mLastDispatchedIsInPictureInPictureMode=");
+                writer.println(mLastDispatchedIsInPictureInPictureMode);
         writer.print(innerPrefix); writer.print("mChangingConfigurations=");
                 writer.println(mChangingConfigurations);
         writer.print(innerPrefix); writer.print("mCurrentConfig=");
@@ -8078,6 +8086,7 @@ public class Activity extends ContextThemeWrapper
         if (mWindow != null) {
             mWindow.onMultiWindowModeChanged();
         }
+        mLastDispatchedIsInMultiWindowMode = isInMultiWindowMode;
         onMultiWindowModeChanged(isInMultiWindowMode, newConfig);
     }
 
@@ -8090,6 +8099,7 @@ public class Activity extends ContextThemeWrapper
         if (mWindow != null) {
             mWindow.onPictureInPictureModeChanged(isInPictureInPictureMode);
         }
+        mLastDispatchedIsInPictureInPictureMode = isInPictureInPictureMode;
         onPictureInPictureModeChanged(isInPictureInPictureMode, newConfig);
     }
 
diff --git a/services/core/java/com/android/server/wm/TaskStack.java b/services/core/java/com/android/server/wm/TaskStack.java
index 114a56feaf73e..858d198ccd5f0 100644
--- a/services/core/java/com/android/server/wm/TaskStack.java
+++ b/services/core/java/com/android/server/wm/TaskStack.java
@@ -1747,6 +1747,11 @@ public class TaskStack extends WindowContainer<Task> implements
             if (toBounds.width() == fromBounds.width()
                     && toBounds.height() == fromBounds.height()) {
                 intendedAnimationType = BoundsAnimationController.BOUNDS;
+            } else if (!fromFullscreen && !toBounds.equals(fromBounds)) {
+                // intendedAnimationType may have been reset at the end of RecentsAnimation,
+                // force it to BOUNDS type if we know for certain we're animating to
+                // a different bounds, especially for expand and collapse of PiP window.
+                intendedAnimationType = BoundsAnimationController.BOUNDS;
             }
         }