From 126cbc410d8e8f16ff836c030fa6b62f497cc213 Mon Sep 17 00:00:00 2001
From: woals4815 <ckrt4815@gmail.com>
Date: Sun, 15 Jun 2025 17:23:12 +0900
Subject: [PATCH 1/4] Add contentChanged in ApnsPayload interface

---
 src/messaging/messaging-api.ts | 18 ++++++++++++++++++
 1 file changed, 18 insertions(+)

diff --git a/src/messaging/messaging-api.ts b/src/messaging/messaging-api.ts
index d0c5d5af7e..5992518b04 100644
--- a/src/messaging/messaging-api.ts
+++ b/src/messaging/messaging-api.ts
@@ -308,6 +308,12 @@ export interface Aps {
    */
   mutableContent?: boolean;
 
+  /**
+   * Specifies whether to set the `content-changed` property on the message
+   * so the clients can modify the notification via app extensions.
+   */
+  contentChanged?: boolean;
+
   /**
    * Type of the notification.
    */
@@ -948,6 +954,18 @@ export interface MessagingOptions {
    */
   contentAvailable?: boolean;
 
+  /**
+   * On iOS, use this field to represent `content-changed` in the APNs payload.
+   *
+   * See {@link https://developer.apple.com/documentation/widgetkit/updating-widgets-with-widgetkit-push-notifications |
+   * Updating Widgets with WidgetKit Push Notifications} for more information.
+   *
+   * On Android and web, this field is ignored.
+   *
+   * **Default value:** `false`
+   */
+  contentChanged?: boolean;
+
   /**
    * The package name of the application which the registration tokens must match
    * in order to receive the message.

From f5896671dd6fb2d7f78b090445c83c801d97317f Mon Sep 17 00:00:00 2001
From: woals4815 <ckrt4815@gmail.com>
Date: Sun, 15 Jun 2025 17:25:57 +0900
Subject: [PATCH 2/4] Add validating contentChanged logic

---
 src/messaging/messaging-internal.ts | 10 ++++++++++
 1 file changed, 10 insertions(+)

diff --git a/src/messaging/messaging-internal.ts b/src/messaging/messaging-internal.ts
index c41f93a923..f32bf7c280 100644
--- a/src/messaging/messaging-internal.ts
+++ b/src/messaging/messaging-internal.ts
@@ -274,6 +274,7 @@ function validateAps(aps: Aps): void {
     contentAvailable: 'content-available',
     mutableContent: 'mutable-content',
     threadId: 'thread-id',
+    contentChanged: 'content-changed',
   };
   Object.keys(propertyMappings).forEach((key) => {
     if (key in aps && propertyMappings[key] in aps) {
@@ -300,6 +301,15 @@ function validateAps(aps: Aps): void {
       delete aps['mutable-content'];
     }
   }
+
+  const contentChanged = aps['content-changed'];
+  if (typeof contentChanged !== 'undefined' && contentChanged !== 1) {
+    if (contentChanged === true) {
+      aps['content-changed'] = 1;
+    } else {
+      delete aps['content-changed'];
+    }
+  }
 }
 
 function validateApsSound(sound: string | CriticalSound | undefined): void {

From 31c70cff5e3a979ff753dde2506040ee79febaa6 Mon Sep 17 00:00:00 2001
From: woals4815 <ckrt4815@gmail.com>
Date: Sun, 15 Jun 2025 17:26:23 +0900
Subject: [PATCH 3/4] Add contentChanged in MessagingOptions

---
 etc/firebase-admin.messaging.api.md | 1 +
 1 file changed, 1 insertion(+)

diff --git a/etc/firebase-admin.messaging.api.md b/etc/firebase-admin.messaging.api.md
index 1ad50f85f6..3c1c73c5b7 100644
--- a/etc/firebase-admin.messaging.api.md
+++ b/etc/firebase-admin.messaging.api.md
@@ -309,6 +309,7 @@ export interface MessagingOptions {
     priority?: string;
     restrictedPackageName?: string;
     timeToLive?: number;
+    contentChanged?: boolean
 }
 
 // @public

From bce9031ed141cb565ec13480e24e1a2603bd18d9 Mon Sep 17 00:00:00 2001
From: woals4815 <ckrt4815@gmail.com>
Date: Sun, 15 Jun 2025 17:26:38 +0900
Subject: [PATCH 4/4] Add unit test case for contentChanged property

---
 test/unit/messaging/messaging.spec.ts | 40 +++++++++++++++++++++++++++
 1 file changed, 40 insertions(+)

diff --git a/test/unit/messaging/messaging.spec.ts b/test/unit/messaging/messaging.spec.ts
index 9e8d1ea814..58c34b1c85 100644
--- a/test/unit/messaging/messaging.spec.ts
+++ b/test/unit/messaging/messaging.spec.ts
@@ -2192,6 +2192,7 @@ describe('Messaging', () => {
                 category: 'test.category',
                 contentAvailable: true,
                 mutableContent: true,
+                contentChanged: true,
                 threadId: 'thread.id',
               },
               customKey1: 'custom.value',
@@ -2229,6 +2230,7 @@ describe('Messaging', () => {
                 'category': 'test.category',
                 'content-available': 1,
                 'mutable-content': 1,
+                'content-changed': 1,
                 'thread-id': 'thread.id',
               },
               customKey1: 'custom.value',
@@ -2380,6 +2382,44 @@ describe('Messaging', () => {
           },
         },
       },
+      {
+        label: 'APNS contentChanged explicitly false',
+        req: {
+          apns: {
+            payload: {
+              aps: {
+                contentChanged: false,
+              },
+            },
+          },
+        },
+        expectedReq: {
+          apns: {
+            payload: {
+              aps: {},
+            },
+          },
+        },
+      },
+      {
+        label: 'APNS contentChanged set explicitly',
+        req: {
+          apns: {
+            payload: {
+              aps: {
+                'content-changed': 1,
+              },
+            },
+          },
+        },
+        expectedReq: {
+          apns: {
+            payload: {
+              aps: { 'content-changed': 1 },
+            },
+          },
+        },
+      },
       {
         label: 'APNS custom fields',
         req: {