Discard jobs that fail to deserialize

app/jobs/application_job.rb

@@ -1,7 +1,7 @@
 class ApplicationJob < ActiveJob::Base
-  # Automatically retry jobs that encountered a deadlock
-  # retry_on ActiveRecord::Deadlocked
-
-  # Most jobs are safe to ignore if the underlying records are no longer available
-  # discard_on ActiveJob::DeserializationError
+  def perform_now(*)
+    super
+  rescue ActiveJob::DeserializationError => e
+    raise unless e.cause.is_a?(ActiveRecord::RecordNotFound)
+  end
 end

app/jobs/mail_delivery_job.rb

@@ -0,0 +1,7 @@
+class MailDeliveryJob < ActionMailer::MailDeliveryJob
+  def perform_now(*)
+    super
+  rescue ActiveJob::DeserializationError => e
+    raise unless e.cause.is_a?(ActiveRecord::RecordNotFound)
+  end
+end

app/mailers/application_mailer.rb

@@ -1,3 +1,3 @@
 class ApplicationMailer < ActionMailer::Base
-  self.delivery_job = ActionMailer::MailDeliveryJob
+  self.delivery_job = MailDeliveryJob
 end