diff --git a/app/services/messages/webhook_content_normalizer.rb b/app/services/messages/webhook_content_normalizer.rb
index b45f83ad0..5fa66fe9c 100644
--- a/app/services/messages/webhook_content_normalizer.rb
+++ b/app/services/messages/webhook_content_normalizer.rb
@@ -1,10 +1,11 @@
 # Strips CommonMark hard line breaks from stored markdown source (backslash before newline).
 # ProseMirror / the dashboard editor emits this form so soft breaks survive as markdown;
 # webhook consumers expect plain newlines without a visible backslash (e.g. WhatsApp gateways).
+# Also strips trailing newlines introduced by TipTap/ProseMirror trailing paragraph nodes.
 class Messages::WebhookContentNormalizer
   def self.normalize(text)
     return text if text.blank?
 
-    text.gsub(/\\\r?\n/, "\n")
+    text.gsub(/\\\r?\n/, "\n").sub(/(\r?\n)+\z/, '')
   end
 end
diff --git a/spec/services/messages/webhook_content_normalizer_spec.rb b/spec/services/messages/webhook_content_normalizer_spec.rb
new file mode 100644
index 000000000..ca5023b9d
--- /dev/null
+++ b/spec/services/messages/webhook_content_normalizer_spec.rb
@@ -0,0 +1,41 @@
+require 'rails_helper'
+
+RSpec.describe Messages::WebhookContentNormalizer do
+  describe '.normalize' do
+    it 'returns nil unchanged' do
+      expect(described_class.normalize(nil)).to be_nil
+    end
+
+    it 'returns blank string unchanged' do
+      expect(described_class.normalize('')).to eq('')
+    end
+
+    it 'strips trailing newlines added by TipTap/ProseMirror' do
+      expect(described_class.normalize("hello\n\n\n")).to eq('hello')
+    end
+
+    it 'preserves intentional trailing spaces' do
+      expect(described_class.normalize("hello   \n\n")).to eq('hello   ')
+    end
+
+    it 'replaces CommonMark hard line breaks (backslash-newline) with plain newlines' do
+      expect(described_class.normalize("hello\\\nworld")).to eq("hello\nworld")
+    end
+
+    it 'replaces CommonMark hard line breaks with CRLF with plain newlines' do
+      expect(described_class.normalize("hello\\\r\nworld")).to eq("hello\nworld")
+    end
+
+    it 'preserves intentional internal newlines' do
+      expect(described_class.normalize("line one\nline two")).to eq("line one\nline two")
+    end
+
+    it 'strips trailing CRLF newlines without leaving dangling carriage returns' do
+      expect(described_class.normalize("hello\r\n\r\n")).to eq('hello')
+    end
+
+    it 'handles both hard line breaks and trailing newlines together' do
+      expect(described_class.normalize("hello\\\nworld\n\n\n")).to eq("hello\nworld")
+    end
+  end
+end