diff --git a/app/channels/application_cable/channel.rb b/app/channels/application_cable/channel.rb
index c02f7466..b2939137 100644
--- a/app/channels/application_cable/channel.rb
+++ b/app/channels/application_cable/channel.rb
@@ -2,14 +2,12 @@
 
 module ApplicationCable
   class Channel < ActionCable::Channel::Base
-    @streaming_confirmation_callback = -> {}
-
     def ensure_confirmation_sent
       # Currently, we are required to overwrite this ActionCable method.
       # Once called and the subscription confirmation is sent, we call the custom callback.
       # See https://github.com/rails/rails/issues/25333.
       super
-      @streaming_confirmation_callback.call if subscription_confirmation_sent?
+      @streaming_confirmation_callback.call if subscription_confirmation_sent? && @streaming_confirmation_callback.present?
     end
 
     def send_after_streaming_confirmed(&block)