diff --git a/packages/SystemUI/src/com/android/systemui/accessibility/WindowMagnificationSettings.java b/packages/SystemUI/src/com/android/systemui/accessibility/WindowMagnificationSettings.java
index d0ff9f82db927..d27087d349de7 100644
--- a/packages/SystemUI/src/com/android/systemui/accessibility/WindowMagnificationSettings.java
+++ b/packages/SystemUI/src/com/android/systemui/accessibility/WindowMagnificationSettings.java
@@ -79,7 +79,8 @@ class WindowMagnificationSettings implements MagnificationGestureDetector.OnGest
     private final Runnable mWindowInsetChangeRunnable;
     private final SfVsyncFrameCallbackProvider mSfVsyncFrameProvider;
 
-    private final LayoutParams mParams;
+    @VisibleForTesting
+    final LayoutParams mParams;
     @VisibleForTesting
     final Rect mDraggableWindowBounds = new Rect();
     private boolean mIsVisible = false;
@@ -529,7 +530,6 @@ class WindowMagnificationSettings implements MagnificationGestureDetector.OnGest
             // CONFIG_FONT_SCALE: font size change
             // CONFIG_LOCALE: language change
             // CONFIG_DENSITY: display size change
-
             mParams.accessibilityTitle = getAccessibilityWindowTitle(mContext);
 
             boolean showSettingPanelAfterConfigChange = mIsVisible;
@@ -541,16 +541,13 @@ class WindowMagnificationSettings implements MagnificationGestureDetector.OnGest
             return;
         }
 
-        if ((configDiff & ActivityInfo.CONFIG_ORIENTATION) != 0) {
-            final Rect previousDraggableBounds = new Rect(mDraggableWindowBounds);
+        if ((configDiff & ActivityInfo.CONFIG_ORIENTATION) != 0
+                || (configDiff & ActivityInfo.CONFIG_SCREEN_SIZE) != 0) {
             mDraggableWindowBounds.set(getDraggableWindowBounds());
-            // Keep the Y position with the same height ratio before the window bounds and
-            // draggable bounds are changed.
-            final float windowHeightFraction = (float) (mParams.y - previousDraggableBounds.top)
-                    / previousDraggableBounds.height();
-            mParams.y = (int) (windowHeightFraction * mDraggableWindowBounds.height())
-                    + mDraggableWindowBounds.top;
-            return;
+            // reset the panel position to the right-bottom corner
+            mParams.x = mDraggableWindowBounds.right;
+            mParams.y = mDraggableWindowBounds.bottom;
+            updateButtonViewLayoutIfNeeded();
         }
     }
 
@@ -562,7 +559,8 @@ class WindowMagnificationSettings implements MagnificationGestureDetector.OnGest
         mDraggableWindowBounds.set(newBounds);
     }
 
-    private void updateButtonViewLayoutIfNeeded() {
+    @VisibleForTesting
+    void updateButtonViewLayoutIfNeeded() {
         if (mIsVisible) {
             mParams.x = MathUtils.constrain(mParams.x, mDraggableWindowBounds.left,
                     mDraggableWindowBounds.right);
diff --git a/packages/SystemUI/tests/src/com/android/systemui/accessibility/WindowMagnificationSettingsTest.java b/packages/SystemUI/tests/src/com/android/systemui/accessibility/WindowMagnificationSettingsTest.java
index ce96708039aed..df08decdfd3db 100644
--- a/packages/SystemUI/tests/src/com/android/systemui/accessibility/WindowMagnificationSettingsTest.java
+++ b/packages/SystemUI/tests/src/com/android/systemui/accessibility/WindowMagnificationSettingsTest.java
@@ -37,6 +37,7 @@ import android.annotation.IdRes;
 import android.content.Context;
 import android.content.pm.ActivityInfo;
 import android.database.ContentObserver;
+import android.graphics.Rect;
 import android.os.UserHandle;
 import android.provider.Settings;
 import android.testing.AndroidTestingRunner;
@@ -49,6 +50,7 @@ import android.widget.Button;
 import android.widget.CompoundButton;
 import android.widget.LinearLayout;
 
+import androidx.test.InstrumentationRegistry;
 import androidx.test.filters.SmallTest;
 
 import com.android.internal.graphics.SfVsyncFrameCallbackProvider;
@@ -65,7 +67,7 @@ import org.mockito.MockitoAnnotations;
 
 @SmallTest
 @RunWith(AndroidTestingRunner.class)
-@TestableLooper.RunWithLooper(setAsMainLooper = true)
+@TestableLooper.RunWithLooper
 public class WindowMagnificationSettingsTest extends SysuiTestCase {
 
     private static final int MAGNIFICATION_SIZE_SMALL = 1;
@@ -274,6 +276,39 @@ public class WindowMagnificationSettingsTest extends SysuiTestCase {
         assertThat(magnifierMediumButton.isSelected()).isTrue();
     }
 
+    @Test
+    public void onScreenSizeChanged_resetPositionToRightBottomCorner() {
+        setupMagnificationCapabilityAndMode(
+                /* capability= */ ACCESSIBILITY_MAGNIFICATION_MODE_ALL,
+                /* mode= */ ACCESSIBILITY_MAGNIFICATION_MODE_WINDOW);
+        mWindowMagnificationSettings.showSettingPanel();
+
+        // move the panel to the center of draggable window bounds
+        mWindowMagnificationSettings.mParams.x =
+                mWindowMagnificationSettings.mDraggableWindowBounds.centerX();
+        mWindowMagnificationSettings.mParams.y =
+                mWindowMagnificationSettings.mDraggableWindowBounds.centerY();
+        mWindowMagnificationSettings.updateButtonViewLayoutIfNeeded();
+
+        final Rect testWindowBounds = new Rect(
+                mWindowManager.getCurrentWindowMetrics().getBounds());
+        testWindowBounds.set(testWindowBounds.left, testWindowBounds.top,
+                testWindowBounds.right + 200, testWindowBounds.bottom + 50);
+        mWindowManager.setWindowBounds(testWindowBounds);
+
+        InstrumentationRegistry.getInstrumentation().runOnMainSync(() -> {
+            mWindowMagnificationSettings.onConfigurationChanged(ActivityInfo.CONFIG_SCREEN_SIZE);
+        });
+
+        // the panel position should be reset to the bottom-right corner
+        assertEquals(
+                mWindowMagnificationSettings.mParams.x,
+                mWindowMagnificationSettings.mDraggableWindowBounds.right);
+        assertEquals(
+                mWindowMagnificationSettings.mParams.y,
+                mWindowMagnificationSettings.mDraggableWindowBounds.bottom);
+    }
+
     @Test
     public void showSettingsPanel_observerRegistered() {
         setupMagnificationCapabilityAndMode(