diff --git a/services/core/java/com/android/server/wm/LaunchParamsController.java b/services/core/java/com/android/server/wm/LaunchParamsController.java
index 56e1187d51da2..a0074a2d760c3 100644
--- a/services/core/java/com/android/server/wm/LaunchParamsController.java
+++ b/services/core/java/com/android/server/wm/LaunchParamsController.java
@@ -144,11 +144,11 @@ class LaunchParamsController {
                         mTmpParams.mPreferredTaskDisplayArea, true /* onTop */);
             }
 
-            if (mTmpParams.hasWindowingMode()
-                    && mTmpParams.mWindowingMode != task.getRootTask().getWindowingMode()) {
+            if (mTmpParams.hasWindowingMode() && task.isRootTask()
+                    && mTmpParams.mWindowingMode != task.getWindowingMode()) {
                 final int activityType = activity != null
                         ? activity.getActivityType() : task.getActivityType();
-                task.getRootTask().setWindowingMode(task.getDisplayArea().validateWindowingMode(
+                task.setWindowingMode(task.getDisplayArea().validateWindowingMode(
                         mTmpParams.mWindowingMode, activity, task, activityType));
             }
 
diff --git a/services/core/java/com/android/server/wm/TaskDisplayArea.java b/services/core/java/com/android/server/wm/TaskDisplayArea.java
index 696e1cafae95b..ce99102fddb33 100644
--- a/services/core/java/com/android/server/wm/TaskDisplayArea.java
+++ b/services/core/java/com/android/server/wm/TaskDisplayArea.java
@@ -1305,10 +1305,9 @@ final class TaskDisplayArea extends DisplayArea<Task> {
             final int windowingMode = windowingModes[j];
             for (int i = getStackCount() - 1; i >= 0; --i) {
                 final Task stack = getStackAt(i);
-                if (!stack.isActivityTypeStandardOrUndefined()) {
-                    continue;
-                }
-                if (stack.getWindowingMode() != windowingMode) {
+                if (stack.mCreatedByOrganizer
+                        || !stack.isActivityTypeStandardOrUndefined()
+                        || stack.getWindowingMode() != windowingMode) {
                     continue;
                 }
                 stacks.add(stack);
diff --git a/services/tests/wmtests/src/com/android/server/wm/LaunchParamsControllerTests.java b/services/tests/wmtests/src/com/android/server/wm/LaunchParamsControllerTests.java
index 820eca4a49a89..bc7516f6514f7 100644
--- a/services/tests/wmtests/src/com/android/server/wm/LaunchParamsControllerTests.java
+++ b/services/tests/wmtests/src/com/android/server/wm/LaunchParamsControllerTests.java
@@ -19,6 +19,7 @@ package com.android.server.wm;
 import static android.app.WindowConfiguration.WINDOWING_MODE_FREEFORM;
 import static android.app.WindowConfiguration.WINDOWING_MODE_FULLSCREEN;
 import static android.app.WindowConfiguration.WINDOWING_MODE_PINNED;
+import static android.app.WindowConfiguration.WINDOWING_MODE_SPLIT_SCREEN_SECONDARY;
 import static android.view.Display.INVALID_DISPLAY;
 
 import static com.android.dx.mockito.inline.extended.ExtendedMockito.any;
@@ -318,6 +319,29 @@ public class LaunchParamsControllerTests extends WindowTestsBase {
         assertEquals(windowingMode, afterWindowMode);
     }
 
+    /**
+     * Ensures that {@link LaunchParamsModifier} doesn't alter non-root tasks' windowingMode.
+     */
+    @Test
+    public void testLayoutNonRootTaskWindowingModeChange() {
+        final LaunchParams params = new LaunchParams();
+        final int windowingMode = WINDOWING_MODE_FREEFORM;
+        params.mWindowingMode = windowingMode;
+        final InstrumentedPositioner positioner = new InstrumentedPositioner(RESULT_DONE, params);
+        final Task task = new TaskBuilder(mAtm.mStackSupervisor).setCreateParentTask(true).build();
+        task.getRootTask().setWindowingMode(WINDOWING_MODE_SPLIT_SCREEN_SECONDARY);
+
+        mController.registerModifier(positioner);
+
+        final int beforeWindowMode = task.getWindowingMode();
+        assertNotEquals(windowingMode, beforeWindowMode);
+
+        mController.layoutTask(task, null /* windowLayout */);
+
+        final int afterWindowMode = task.getWindowingMode();
+        assertEquals(afterWindowMode, beforeWindowMode);
+    }
+
     /**
      * Ensures that {@link LaunchParamsModifier} requests specifying bounds during
      * layout are honored if window is in freeform.