diff --git a/packages/SystemUI/res/color/qs_dialog_btn_filled_background.xml b/packages/SystemUI/res/color/qs_dialog_btn_filled_background.xml
new file mode 100644
index 0000000000000..40bab5ed08f25
--- /dev/null
+++ b/packages/SystemUI/res/color/qs_dialog_btn_filled_background.xml
@@ -0,0 +1,23 @@
+<?xml version="1.0" encoding="utf-8"?>
+<!--
+  ~ Copyright (C) 2023 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.
+  -->
+<selector xmlns:android="http://schemas.android.com/apk/res/android"
+          xmlns:androidprv="http://schemas.android.com/apk/prv/res/android">
+    <item android:state_enabled="false"
+          android:color="?androidprv:attr/materialColorPrimary"
+          android:alpha="0.30"/>
+    <item android:color="?androidprv:attr/materialColorPrimary"/>
+</selector>
\ No newline at end of file
diff --git a/packages/SystemUI/res/color/qs_dialog_btn_filled_text_color.xml b/packages/SystemUI/res/color/qs_dialog_btn_filled_text_color.xml
new file mode 100644
index 0000000000000..e76ad991a92c5
--- /dev/null
+++ b/packages/SystemUI/res/color/qs_dialog_btn_filled_text_color.xml
@@ -0,0 +1,23 @@
+<?xml version="1.0" encoding="utf-8"?>
+<!--
+  ~ Copyright (C) 2023 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.
+  -->
+<selector xmlns:android="http://schemas.android.com/apk/res/android"
+          xmlns:androidprv="http://schemas.android.com/apk/prv/res/android">
+    <item android:state_enabled="false"
+          android:color="?androidprv:attr/materialColorOnPrimary"
+          android:alpha="0.30"/>
+    <item android:color="?androidprv:attr/materialColorOnPrimary"/>
+</selector>
\ No newline at end of file
diff --git a/packages/SystemUI/res/drawable/qs_dialog_btn_filled.xml b/packages/SystemUI/res/drawable/qs_dialog_btn_filled.xml
index c4e45bf2c2237..9bc8b53b308eb 100644
--- a/packages/SystemUI/res/drawable/qs_dialog_btn_filled.xml
+++ b/packages/SystemUI/res/drawable/qs_dialog_btn_filled.xml
@@ -15,7 +15,6 @@
   ~ limitations under the License.
   -->
 <inset xmlns:android="http://schemas.android.com/apk/res/android"
-       xmlns:androidprv="http://schemas.android.com/apk/prv/res/android"
        android:insetTop="@dimen/dialog_button_vertical_inset"
        android:insetBottom="@dimen/dialog_button_vertical_inset">
     <ripple android:color="?android:attr/colorControlHighlight">
@@ -28,7 +27,7 @@
         <item>
             <shape android:shape="rectangle">
                 <corners android:radius="?android:attr/buttonCornerRadius"/>
-                <solid android:color="?androidprv:attr/materialColorPrimary"/>
+                <solid android:color="@color/qs_dialog_btn_filled_background"/>
                 <padding android:left="@dimen/dialog_button_horizontal_padding"
                          android:top="@dimen/dialog_button_vertical_padding"
                          android:right="@dimen/dialog_button_horizontal_padding"
diff --git a/packages/SystemUI/res/values/styles.xml b/packages/SystemUI/res/values/styles.xml
index 31f40e99e91c2..1c46a91e5d29a 100644
--- a/packages/SystemUI/res/values/styles.xml
+++ b/packages/SystemUI/res/values/styles.xml
@@ -1116,7 +1116,7 @@
     <style name="Widget.Dialog.Button">
         <item name="android:buttonCornerRadius">28dp</item>
         <item name="android:background">@drawable/qs_dialog_btn_filled</item>
-        <item name="android:textColor">?androidprv:attr/materialColorOnPrimary</item>
+        <item name="android:textColor">@color/qs_dialog_btn_filled_text_color</item>
         <item name="android:textSize">14sp</item>
         <item name="android:lineHeight">20sp</item>
         <item name="android:fontFamily">@*android:string/config_bodyFontFamilyMedium</item>
diff --git a/packages/SystemUI/src/com/android/systemui/accessibility/fontscaling/FontScalingDialog.kt b/packages/SystemUI/src/com/android/systemui/accessibility/fontscaling/FontScalingDialog.kt
index 783460c325fad..0ef256d411578 100644
--- a/packages/SystemUI/src/com/android/systemui/accessibility/fontscaling/FontScalingDialog.kt
+++ b/packages/SystemUI/src/com/android/systemui/accessibility/fontscaling/FontScalingDialog.kt
@@ -145,6 +145,8 @@ class FontScalingDialog(
      */
     @MainThread
     fun updateFontScaleDelayed(delayMsFromSource: Long) {
+        doneButton.isEnabled = false
+
         var delayMs = delayMsFromSource
         if (systemClock.elapsedRealtime() - lastUpdateTime < MIN_UPDATE_INTERVAL_MS) {
             delayMs += MIN_UPDATE_INTERVAL_MS
@@ -197,17 +199,22 @@ class FontScalingDialog(
             title.post {
                 title.setTextAppearance(R.style.TextAppearance_Dialog_Title)
                 doneButton.setTextAppearance(R.style.Widget_Dialog_Button)
+                doneButton.isEnabled = true
             }
         }
     }
 
     @WorkerThread
     fun updateFontScale() {
-        systemSettings.putStringForUser(
-            Settings.System.FONT_SCALE,
-            strEntryValues[lastProgress.get()],
-            userTracker.userId
-        )
+        if (
+            !systemSettings.putStringForUser(
+                Settings.System.FONT_SCALE,
+                strEntryValues[lastProgress.get()],
+                userTracker.userId
+            )
+        ) {
+            title.post { doneButton.isEnabled = true }
+        }
     }
 
     @WorkerThread
diff --git a/packages/SystemUI/tests/src/com/android/systemui/accessibility/fontscaling/FontScalingDialogTest.kt b/packages/SystemUI/tests/src/com/android/systemui/accessibility/fontscaling/FontScalingDialogTest.kt
index d5e6881500bca..7b99314692b4a 100644
--- a/packages/SystemUI/tests/src/com/android/systemui/accessibility/fontscaling/FontScalingDialogTest.kt
+++ b/packages/SystemUI/tests/src/com/android/systemui/accessibility/fontscaling/FontScalingDialogTest.kt
@@ -15,11 +15,13 @@
  */
 package com.android.systemui.accessibility.fontscaling
 
+import android.content.res.Configuration
 import android.os.Handler
 import android.provider.Settings
 import android.testing.AndroidTestingRunner
 import android.testing.TestableLooper
 import android.view.ViewGroup
+import android.widget.Button
 import android.widget.SeekBar
 import androidx.test.filters.SmallTest
 import com.android.systemui.R
@@ -61,6 +63,7 @@ class FontScalingDialogTest : SysuiTestCase() {
     private lateinit var secureSettings: SecureSettings
     private lateinit var systemClock: FakeSystemClock
     private lateinit var backgroundDelayableExecutor: FakeExecutor
+    private lateinit var testableLooper: TestableLooper
     private val fontSizeValueArray: Array<String> =
         mContext
             .getResources()
@@ -73,7 +76,8 @@ class FontScalingDialogTest : SysuiTestCase() {
     @Before
     fun setUp() {
         MockitoAnnotations.initMocks(this)
-        val mainHandler = Handler(TestableLooper.get(this).getLooper())
+        testableLooper = TestableLooper.get(this)
+        val mainHandler = Handler(testableLooper.looper)
         systemSettings = FakeSettings()
         // Guarantee that the systemSettings always starts with the default font scale.
         systemSettings.putFloatForUser(Settings.System.FONT_SCALE, 1.0f, userTracker.userId)
@@ -286,4 +290,26 @@ class FontScalingDialogTest : SysuiTestCase() {
         verify(fontScalingDialog).createTextPreview(/* index= */ 0)
         fontScalingDialog.dismiss()
     }
+
+    @Test
+    fun changeFontSize_buttonIsDisabledBeforeFontSizeChangeFinishes() {
+        fontScalingDialog.show()
+
+        val iconEndFrame: ViewGroup = fontScalingDialog.findViewById(R.id.icon_end_frame)!!
+        val doneButton: Button = fontScalingDialog.findViewById(com.android.internal.R.id.button1)!!
+
+        iconEndFrame.performClick()
+        backgroundDelayableExecutor.runAllReady()
+        backgroundDelayableExecutor.advanceClockToNext()
+        backgroundDelayableExecutor.runAllReady()
+
+        // Verify that the button is disabled before receiving onConfigurationChanged
+        assertThat(doneButton.isEnabled).isFalse()
+
+        val config = Configuration()
+        config.fontScale = 1.15f
+        fontScalingDialog.onConfigurationChanged(config)
+        testableLooper.processAllMessages()
+        assertThat(doneButton.isEnabled).isTrue()
+    }
 }