diff --git a/actionpack/lib/action_controller/metal/live.rb b/actionpack/lib/action_controller/metal/live.rb
index 2f4c8fb83cd07..6d89b9d49abc7 100644
--- a/actionpack/lib/action_controller/metal/live.rb
+++ b/actionpack/lib/action_controller/metal/live.rb
@@ -141,7 +141,7 @@ def initialize(response)
         @cv = new_cond
         @aborted = false
         @ignore_disconnect = false
-        super(response, SizedQueue.new(10))
+        super(response, Rails.env.test? ? Queue.new : SizedQueue.new(10))
       end
 
       def write(string)
diff --git a/actionpack/test/controller/live_stream_test.rb b/actionpack/test/controller/live_stream_test.rb
index 431fe90b23a24..6811fd3a36393 100644
--- a/actionpack/test/controller/live_stream_test.rb
+++ b/actionpack/test/controller/live_stream_test.rb
@@ -330,25 +330,27 @@ def test_async_stream
     end
 
     def test_abort_with_full_buffer
-      @controller.latch = Concurrent::CountDownLatch.new
-      @controller.error_latch = Concurrent::CountDownLatch.new
-
-      capture_log_output do |output|
-        get :overfill_buffer_and_die, format: "plain"
-
-        t = Thread.new(response) { |resp|
-          resp.await_commit
-          _, _, body = resp.to_a
-          body.each do
-            @controller.latch.wait
-            body.close
-            break
-          end
-        }
-
-        t.join
-        @controller.error_latch.wait
-        assert_match "Error while streaming", output.rewind && output.read
+      Rails.stub(:env, ActiveSupport::StringInquirer.new("production")) do
+        @controller.latch = Concurrent::CountDownLatch.new
+        @controller.error_latch = Concurrent::CountDownLatch.new
+
+        capture_log_output do |output|
+          get :overfill_buffer_and_die, format: "plain"
+
+          t = Thread.new(response) { |resp|
+            resp.await_commit
+            _, _, body = resp.to_a
+            body.each do
+              @controller.latch.wait
+              body.close
+              break
+            end
+          }
+
+          t.join
+          @controller.error_latch.wait
+          assert_match "Error while streaming", output.rewind && output.read
+        end
       end
     end