diff --git a/actiontext/lib/action_text/content.rb b/actiontext/lib/action_text/content.rb
index 6126a4de49..ab8fc05c8c 100644
--- a/actiontext/lib/action_text/content.rb
+++ b/actiontext/lib/action_text/content.rb
@@ -84,7 +84,7 @@ module ActionText
     end
 
     def to_rendered_html_with_layout
-      render partial: "action_text/content/layout", locals: { content: self }
+      render partial: "action_text/content/layout", formats: :html, locals: { content: self }
     end
 
     def to_s
diff --git a/actiontext/test/dummy/app/views/messages/show.json.erb b/actiontext/test/dummy/app/views/messages/show.json.erb
new file mode 100644
index 0000000000..7db887350a
--- /dev/null
+++ b/actiontext/test/dummy/app/views/messages/show.json.erb
@@ -0,0 +1,5 @@
+{
+  "id": <%= @message.id %>,
+  "subject": "<%= j @message.subject %>",
+  "content": "<%= j @message.content %>"
+}
diff --git a/actiontext/test/integration/controller_render_test.rb b/actiontext/test/integration/controller_render_test.rb
index 2e8812ed88..b731af4cb3 100644
--- a/actiontext/test/integration/controller_render_test.rb
+++ b/actiontext/test/integration/controller_render_test.rb
@@ -14,6 +14,16 @@ class ActionText::ControllerRenderTest < ActionDispatch::IntegrationTest
     end
   end
 
+  test "renders as HTML when the request format is not HTML" do
+    blob = create_file_blob(filename: "racecar.jpg", content_type: "image/jpg")
+    message = Message.create!(content: ActionText::Content.new.append_attachables(blob))
+
+    host! "loocalhoost"
+    get message_path(message, format: :json)
+    content = Nokogiri::HTML::DocumentFragment.parse(response.parsed_body["content"])
+    assert_select content, "img:match('src', ?)", %r"//loocalhoost/.+/racecar"
+  end
+
   test "resolves partials when controller is namespaced" do
     blob = create_file_blob(filename: "racecar.jpg", content_type: "image/jpg")
     message = Message.create!(content: ActionText::Content.new.append_attachables(blob))