Use ActiveJob to send comment mails

app/jobs/event_comment_mail_job.rb

@@ -0,0 +1,11 @@
+class EventCommentMailJob < ActiveJob::Base
+  queue_as :default
+
+  def perform(comment)
+    conference = comment.commentable.program.conference
+
+    User.comment_notifiable(conference).each do |user|
+      Mailbot.event_comment_mail(comment, user).deliver_now
+    end
+  end
+end