diff --git a/go/quickstep/res/drawable/default_thumbnail.xml b/go/quickstep/res/drawable/default_thumbnail.xml
new file mode 100644
index 0000000..0a2dbf0
--- /dev/null
+++ b/go/quickstep/res/drawable/default_thumbnail.xml
@@ -0,0 +1,22 @@
+<?xml version="1.0" encoding="utf-8"?>
+<!--
+     Copyright (C) 2019 The Android Open Source Project
+
+     Licensed under the Apache License, Version 2.0 (the "License");
+     you may not use this file except in compliance with the License.
+     You may obtain a copy of the License at
+
+          http://www.apache.org/licenses/LICENSE-2.0
+
+     Unless required by applicable law or agreed to in writing, software
+     distributed under the License is distributed on an "AS IS" BASIS,
+     WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+     See the License for the specific language governing permissions and
+     limitations under the License.
+-->
+<shape
+    xmlns:android="http://schemas.android.com/apk/res/android"
+    android:shape="rectangle">
+    <solid android:color="@android:color/darker_gray"/>
+    <corners android:radius="2dp"/>
+</shape>
diff --git a/go/quickstep/res/drawable/empty_content_box.xml b/go/quickstep/res/drawable/empty_content_box.xml
new file mode 100644
index 0000000..a488388
--- /dev/null
+++ b/go/quickstep/res/drawable/empty_content_box.xml
@@ -0,0 +1,23 @@
+<?xml version="1.0" encoding="utf-8"?>
+<!--
+     Copyright (C) 2019 The Android Open Source Project
+
+     Licensed under the Apache License, Version 2.0 (the "License");
+     you may not use this file except in compliance with the License.
+     You may obtain a copy of the License at
+
+          http://www.apache.org/licenses/LICENSE-2.0
+
+     Unless required by applicable law or agreed to in writing, software
+     distributed under the License is distributed on an "AS IS" BASIS,
+     WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+     See the License for the specific language governing permissions and
+     limitations under the License.
+-->
+<shape
+    xmlns:android="http://schemas.android.com/apk/res/android"
+    android:shape="rectangle">
+    <solid android:color="@android:color/transparent"/>
+    <stroke android:color="@android:color/white" android:width="4px"/>
+    <corners android:radius="2dp"/>
+</shape>
\ No newline at end of file
diff --git a/go/quickstep/src/com/android/quickstep/views/TaskItemView.java b/go/quickstep/src/com/android/quickstep/views/TaskItemView.java
index d831b20..0a3fba8 100644
--- a/go/quickstep/src/com/android/quickstep/views/TaskItemView.java
+++ b/go/quickstep/src/com/android/quickstep/views/TaskItemView.java
@@ -16,8 +16,9 @@
 package com.android.quickstep.views;
 
 import android.content.Context;
+import android.content.res.Resources;
 import android.graphics.Bitmap;
-import android.graphics.Color;
+import android.graphics.drawable.BitmapDrawable;
 import android.graphics.drawable.Drawable;
 import android.util.AttributeSet;
 import android.view.View;
@@ -25,6 +26,7 @@
 import android.widget.LinearLayout;
 import android.widget.TextView;
 
+import androidx.annotation.NonNull;
 import androidx.annotation.Nullable;
 
 import com.android.launcher3.R;
@@ -36,14 +38,16 @@
 
     private static final String DEFAULT_LABEL = "...";
     private final Drawable mDefaultIcon;
+    private final Drawable mDefaultThumbnail;
     private TextView mLabelView;
     private ImageView mIconView;
     private ImageView mThumbnailView;
 
     public TaskItemView(Context context, AttributeSet attrs) {
         super(context, attrs);
-        mDefaultIcon = context.getResources().getDrawable(
-                android.R.drawable.sym_def_app_icon, context.getTheme());
+        Resources res = context.getResources();
+        mDefaultIcon = res.getDrawable(android.R.drawable.sym_def_app_icon, context.getTheme());
+        mDefaultThumbnail = res.getDrawable(R.drawable.default_thumbnail, context.getTheme());
     }
 
     @Override
@@ -69,11 +73,7 @@
      * @param label task label
      */
     public void setLabel(@Nullable String label) {
-        if (label == null) {
-            mLabelView.setText(DEFAULT_LABEL);
-            return;
-        }
-        mLabelView.setText(label);
+        mLabelView.setText(getSafeLabel(label));
     }
 
     /**
@@ -86,11 +86,7 @@
         // The icon proper is actually smaller than the drawable and has "padding" on the side for
         // the purpose of drawing the shadow, allowing the icon to pop up, so we need to scale the
         // view if we want the icon to be flush with the bottom of the thumbnail.
-        if (icon == null) {
-            mIconView.setImageDrawable(mDefaultIcon);
-            return;
-        }
-        mIconView.setImageDrawable(icon);
+        mIconView.setImageDrawable(getSafeIcon(icon));
     }
 
     /**
@@ -99,16 +95,23 @@
      * @param thumbnail task thumbnail for the task
      */
     public void setThumbnail(@Nullable Bitmap thumbnail) {
-        if (thumbnail == null) {
-            mThumbnailView.setImageBitmap(null);
-            mThumbnailView.setBackgroundColor(Color.GRAY);
-            return;
-        }
-        mThumbnailView.setBackgroundColor(Color.TRANSPARENT);
-        mThumbnailView.setImageBitmap(thumbnail);
+        mThumbnailView.setImageDrawable(getSafeThumbnail(thumbnail));
     }
 
     public View getThumbnailView() {
         return mThumbnailView;
     }
+
+    private @NonNull Drawable getSafeIcon(@Nullable Drawable icon) {
+        return (icon != null) ? icon : mDefaultIcon;
+    }
+
+    private @NonNull Drawable getSafeThumbnail(@Nullable Bitmap thumbnail) {
+        return (thumbnail != null) ? new BitmapDrawable(getResources(), thumbnail)
+                                   : mDefaultThumbnail;
+    }
+
+    private @NonNull String getSafeLabel(@Nullable String label) {
+        return (label != null) ? label : DEFAULT_LABEL;
+    }
 }
diff --git a/go/quickstep/src/com/android/quickstep/views/TaskLayerDrawable.java b/go/quickstep/src/com/android/quickstep/views/TaskLayerDrawable.java
new file mode 100644
index 0000000..3a23048
--- /dev/null
+++ b/go/quickstep/src/com/android/quickstep/views/TaskLayerDrawable.java
@@ -0,0 +1,90 @@
+/*
+ * Copyright (C) 2019 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.android.quickstep.views;
+
+import android.content.Context;
+import android.graphics.drawable.Drawable;
+import android.graphics.drawable.LayerDrawable;
+
+import androidx.annotation.NonNull;
+
+import com.android.launcher3.R;
+
+/**
+ * A layer drawable for task content that transitions between two drawables by crossfading. Similar
+ * to {@link android.graphics.drawable.TransitionDrawable} but allows callers to control transition
+ * progress and provides a default, empty drawable.
+ */
+public final class TaskLayerDrawable extends LayerDrawable {
+    private final Drawable mEmptyDrawable;
+
+    public TaskLayerDrawable(Context context) {
+        super(new Drawable[0]);
+
+        // Use empty drawable for both layers initially.
+        mEmptyDrawable = context.getResources().getDrawable(
+                R.drawable.empty_content_box, context.getTheme());
+        addLayer(mEmptyDrawable);
+        addLayer(mEmptyDrawable);
+        setTransitionProgress(1.0f);
+    }
+
+    /**
+     * Immediately set the front-most drawable layer.
+     *
+     * @param drawable drawable to set
+     */
+    public void setCurrentDrawable(@NonNull Drawable drawable) {
+        setDrawable(0, drawable);
+    }
+
+    /**
+     * Immediately reset the drawable to showing the empty drawable.
+     */
+    public void resetDrawable() {
+        setCurrentDrawable(mEmptyDrawable);
+    }
+
+    /**
+     * Prepare to start animating the transition by pushing the current drawable to the back and
+     * setting a new drawable to the front layer and making it invisible.
+     *
+     * @param endDrawable drawable to animate to
+     */
+    public void startNewTransition(@NonNull Drawable endDrawable) {
+        Drawable oldDrawable = getDrawable(0);
+        setDrawable(1, oldDrawable);
+        setDrawable(0, endDrawable);
+        setTransitionProgress(0.0f);
+    }
+
+    /**
+     * Set the progress of the transition animation to crossfade the two drawables.
+     *
+     * @param progress current transition progress between 0 (front view invisible) and 1
+     *                 (front view visible)
+     */
+    public void setTransitionProgress(float progress) {
+        if (progress > 1 || progress < 0) {
+            throw new IllegalArgumentException("Transition progress should be between 0 and 1");
+        }
+        int drawableAlpha = (int) (progress * 255);
+        getDrawable(0).setAlpha(drawableAlpha);
+        getDrawable(1).setAlpha(255 - drawableAlpha);
+        invalidateSelf();
+    }
+}
diff --git a/quickstep/recents_ui_overrides/src/com/android/quickstep/TouchInteractionService.java b/quickstep/recents_ui_overrides/src/com/android/quickstep/TouchInteractionService.java
index 3194189..3ea8de0 100644
--- a/quickstep/recents_ui_overrides/src/com/android/quickstep/TouchInteractionService.java
+++ b/quickstep/recents_ui_overrides/src/com/android/quickstep/TouchInteractionService.java
@@ -135,6 +135,12 @@
 
         @Override
         public void onAssistantVisibilityChanged(float visibility) {
+            if (mOverviewComponentObserver == null) {
+                // Save the visibility to be applied when the user is unlocked
+                mPendingAssistantVisibility = visibility;
+                return;
+            }
+
             MAIN_THREAD_EXECUTOR.execute(() -> {
                 mOverviewComponentObserver.getActivityControlHelper()
                         .onAssistantVisibilityChanged(visibility);
@@ -143,6 +149,10 @@
 
         public void onBackAction(boolean completed, int downX, int downY, boolean isButton,
                 boolean gestureSwipeLeft) {
+            if (mOverviewComponentObserver == null) {
+                return;
+            }
+
             final ActivityControlHelper activityControl =
                     mOverviewComponentObserver.getActivityControlHelper();
             UserEventDispatcher.newInstance(getBaseContext()).logActionBack(completed, downX, downY,
@@ -185,6 +195,7 @@
     private InputConsumerController mInputConsumer;
     private SwipeSharedState mSwipeSharedState;
     private boolean mAssistantAvailable;
+    private float mPendingAssistantVisibility = 0;
 
     private boolean mIsUserUnlocked;
     private List<Runnable> mOnUserUnlockedCallbacks;
@@ -337,6 +348,8 @@
         mAM = ActivityManagerWrapper.getInstance();
         mRecentsModel = RecentsModel.INSTANCE.get(this);
         mOverviewComponentObserver = new OverviewComponentObserver(this);
+        mOverviewComponentObserver.getActivityControlHelper().onAssistantVisibilityChanged(
+                mPendingAssistantVisibility);
 
         mOverviewCommandHelper = new OverviewCommandHelper(this, mOverviewComponentObserver);
         mOverviewInteractionState = OverviewInteractionState.INSTANCE.get(this);