fix(facebook): handle messenger sticker attachment type (#14793)

Facebook Messenger sticker messages no longer break message ingestion.
Meta recently changed its webhook payloads so a sticker now arrives as a
new `sticker` attachment type (alongside the existing `image` attachment
during the transition period). Chatwoot didn't recognise `sticker` as a
valid attachment file type, so the webhook job crashed and the message —
and any others in the same batch — failed to sync. Stickers now appear
in the conversation as a single image, just like before.

Fixes https://linear.app/chatwoot/issue/PLA-177

## How to reproduce

1. Connect a Facebook Page inbox.
2. Send a sticker from Messenger to that page.
3. Before this change: the `Webhooks::FacebookEventsJob` raises
`ArgumentError: 'sticker' is not a valid file_type` and the message is
dropped.
4. After this change: the sticker shows up in the conversation as a
single image attachment.

---------

Co-authored-by: Muhsin <12408980+muhsin-k@users.noreply.github.com>
Co-authored-by: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

app/builders/messages/messenger/message_builder.rb

@@ -6,6 +6,11 @@ class Messages::Messenger::MessageBuilder
     return if unsupported_file_type?(attachment['type'])
 
     params = attachment_params(attachment)
+    # During Meta's sticker webhook transition, a sticker message carries both an `image`
+    # and a `sticker` attachment pointing to the same URL. Skip the redundant sticker so it
+    # isn't attached twice, while still storing legitimate duplicate attachments of other types.
+    return if duplicate_sticker?(attachment, params[:external_url])
+
     attachment_obj = @message.attachments.new(params.except(:remote_file_url))
     attachment_obj.save!
     if facebook_reel?(attachment)
@@ -13,10 +18,14 @@ class Messages::Messenger::MessageBuilder
     elsif params[:remote_file_url]
       attach_file(attachment_obj, params[:remote_file_url])
     end
+    fetch_attachment_links(attachment_obj)
+    update_attachment_file_type(attachment_obj)
+  end
+
+  def fetch_attachment_links(attachment_obj)
     fetch_story_link(attachment_obj) if attachment_obj.file_type == 'story_mention'
     fetch_ig_story_link(attachment_obj) if attachment_obj.file_type == 'ig_story'
     fetch_ig_post_link(attachment_obj) if attachment_obj.file_type == 'ig_post'
-    update_attachment_file_type(attachment_obj)
   end
 
   def attach_file(attachment, file_url)
@@ -111,13 +120,20 @@ class Messages::Messenger::MessageBuilder
 
   # Facebook may send attachment types that don't directly match our file_type enum.
   # Map known aliases to their canonical enum values.
-  FACEBOOK_FILE_TYPE_MAP = { reel: :ig_reel }.freeze
+  FACEBOOK_FILE_TYPE_MAP = { reel: :ig_reel, sticker: :image }.freeze
 
   def normalize_file_type(type)
     sym = type.to_sym
     FACEBOOK_FILE_TYPE_MAP.fetch(sym, sym)
   end
 
+  def duplicate_sticker?(attachment, url)
+    return false unless attachment['type'].to_sym == :sticker
+    return false if url.blank?
+
+    @message.attachments.any? { |existing| existing.external_url == url }
+  end
+
   # Facebook sends reel URLs as webpage links (facebook.com/reel/...) rather than
   # direct video URLs. Downloading these yields HTML, not video content.
   def facebook_reel?(attachment)

spec/builders/messages/facebook/message_builder_spec.rb

@@ -140,6 +140,66 @@ describe Messages::Facebook::MessageBuilder do
       end
     end
 
+    context 'when message contains a sticker attachment' do
+      let(:sticker_url) { 'https://scontent.xx.fbcdn.net/sticker.png' }
+      let(:sticker_message_object) do
+        {
+          messaging: {
+            sender: { id: '3383290475046708' },
+            recipient: { id: facebook_channel.page_id },
+            timestamp: 1_772_452_164_516,
+            message: {
+              mid: 'm_sticker_test',
+              attachments: [
+                { type: 'image', payload: { url: sticker_url } },
+                { type: 'sticker', payload: { url: sticker_url } }
+              ]
+            }
+          }
+        }.to_json
+      end
+      let(:sticker_message) { Integrations::Facebook::MessageParser.new(sticker_message_object) }
+
+      before do
+        allow(Koala::Facebook::API).to receive(:new).and_return(fb_object)
+        allow(fb_object).to receive(:get_object).and_return(
+          { first_name: 'Jane', last_name: 'Dae', profile_pic: 'https://chatwoot-assets.local/sample.png' }.with_indifferent_access
+        )
+        stub_request(:get, sticker_url).to_return(status: 200, body: 'sticker_data', headers: { 'Content-Type' => 'image/png' })
+      end
+
+      it 'stores the sticker as a single image attachment' do
+        described_class.new(sticker_message, facebook_channel.inbox).perform
+
+        message = facebook_channel.inbox.messages.find_by(source_id: 'm_sticker_test')
+        expect(message.attachments.count).to eq(1)
+        expect(message.attachments.first.file_type).to eq('image')
+        expect(message.attachments.first.external_url).to eq(sticker_url)
+      end
+
+      it 'keeps duplicate non-sticker attachments that share a URL' do
+        duplicate_image_object = {
+          messaging: {
+            sender: { id: '3383290475046708' },
+            recipient: { id: facebook_channel.page_id },
+            message: {
+              mid: 'm_duplicate_image_test',
+              attachments: [
+                { type: 'image', payload: { url: sticker_url } },
+                { type: 'image', payload: { url: sticker_url } }
+              ]
+            }
+          }
+        }.to_json
+        duplicate_image_message = Integrations::Facebook::MessageParser.new(duplicate_image_object)
+
+        described_class.new(duplicate_image_message, facebook_channel.inbox).perform
+
+        message = facebook_channel.inbox.messages.find_by(source_id: 'm_duplicate_image_test')
+        expect(message.attachments.count).to eq(2)
+      end
+    end
+
     [
       {
         source_id: 'm_fallback_test',