diff --git a/.rubocop_todo.yml b/.rubocop_todo.yml
index 25b573017b8..4d20330e0e2 100644
--- a/.rubocop_todo.yml
+++ b/.rubocop_todo.yml
@@ -54,10 +54,6 @@ Style/ClassEqualityComparison:
     - 'app/helpers/jsonld_helper.rb'
     - 'app/serializers/activitypub/outbox_serializer.rb'
 
-Style/ClassVars:
-  Exclude:
-    - 'config/initializers/devise.rb'
-
 # This cop supports safe autocorrection (--autocorrect).
 # Configuration parameters: AllowedVars.
 Style/FetchEnvVar:
diff --git a/config/initializers/devise.rb b/config/initializers/devise.rb
index f935090efc2..a95c7437fa0 100644
--- a/config/initializers/devise.rb
+++ b/config/initializers/devise.rb
@@ -38,42 +38,25 @@ Warden::Manager.before_logout do |_, warden|
 end
 
 module Devise
-  mattr_accessor :pam_authentication
-  @@pam_authentication = false
-  mattr_accessor :pam_controlled_service
-  @@pam_controlled_service = nil
+  mattr_accessor :pam_authentication, default: false
+  mattr_accessor :pam_controlled_service, default: nil
 
-  mattr_accessor :check_at_sign
-  @@check_at_sign = false
+  mattr_accessor :check_at_sign, default: false
 
-  mattr_accessor :ldap_authentication
-  @@ldap_authentication = false
-  mattr_accessor :ldap_host
-  @@ldap_host = nil
-  mattr_accessor :ldap_port
-  @@ldap_port = nil
-  mattr_accessor :ldap_method
-  @@ldap_method = nil
-  mattr_accessor :ldap_base
-  @@ldap_base = nil
-  mattr_accessor :ldap_uid
-  @@ldap_uid = nil
-  mattr_accessor :ldap_mail
-  @@ldap_mail = nil
-  mattr_accessor :ldap_bind_dn
-  @@ldap_bind_dn = nil
-  mattr_accessor :ldap_password
-  @@ldap_password = nil
-  mattr_accessor :ldap_tls_no_verify
-  @@ldap_tls_no_verify = false
-  mattr_accessor :ldap_search_filter
-  @@ldap_search_filter = nil
-  mattr_accessor :ldap_uid_conversion_enabled
-  @@ldap_uid_conversion_enabled = false
-  mattr_accessor :ldap_uid_conversion_search
-  @@ldap_uid_conversion_search = nil
-  mattr_accessor :ldap_uid_conversion_replace
-  @@ldap_uid_conversion_replace = nil
+  mattr_accessor :ldap_authentication, default: false
+  mattr_accessor :ldap_host, default: nil
+  mattr_accessor :ldap_port, default: nil
+  mattr_accessor :ldap_method, default: nil
+  mattr_accessor :ldap_base, default: nil
+  mattr_accessor :ldap_uid, default: nil
+  mattr_accessor :ldap_mail, default: nil
+  mattr_accessor :ldap_bind_dn, default: nil
+  mattr_accessor :ldap_password, default: nil
+  mattr_accessor :ldap_tls_no_verify, default: false
+  mattr_accessor :ldap_search_filter, default: nil
+  mattr_accessor :ldap_uid_conversion_enabled, default: false
+  mattr_accessor :ldap_uid_conversion_search, default: nil
+  mattr_accessor :ldap_uid_conversion_replace, default: nil
 
   module Strategies
     class PamAuthenticatable