Fix deprecation: returning false in Active Record and Active Model callbacks will not implicitly halt a callback chain

app/models/list.rb

@@ -54,6 +54,6 @@ class List < ActiveRecord::Base
   private
 
   def can_be_destroyed
-    destroyable?
+    throw(:abort) unless destroyable?
   end
 end

changelogs/unreleased/deprecated-callback-false.yml

@@ -0,0 +1,6 @@
+---
+title: 'Fix deprecation: returning false in Active Record and Active Model callbacks
+  will not implicitly halt a callback chain'
+merge_request: 24134
+author: Jasper Maes
+type: other

config/initializers/new_framework_defaults.rb

@@ -22,6 +22,3 @@ ActiveSupport.to_time_preserves_timezone = false
 
 # Require `belongs_to` associations by default. Previous versions had false.
 Rails.application.config.active_record.belongs_to_required_by_default = false
-
-# Do not halt callback chains when a callback returns false. Previous versions had true.
-ActiveSupport.halt_callback_chains_on_return_false = true